Detection of Unnatural Bases Using Raw Nanopore Sequencing Data
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Assessing the prevalence and sequence diversity of Hepatitis B Virus in Sierra Leone with MinION
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University of Cambridge
While Sierra Leone has implemented a robust program to combat HIV infection, there is little to no infrastructure in place for surveillance or treatment of other blood-borne pathogens, such as viral hepatitis. In collaboration with Magbenteh Hospital, University of Makeni Infectious Disease Research Laboratory and the University of Cambridge, over the past 24-months we have collected and screened residual, anonymised blood samples for the presence of viral pathogens, including Hepatitis B Virus (HBV). At present, 7384 samples (2620 male, 4764 female), have been collected and screened. Of this cohort, 7137 have been screened for HBV by qPCR, representing a significantly larger cohort than previously screened within Sierra Leone. Our results found 582 PCR positive patients (8.2%), which is very high considering this represents active infections in the community. We sequenced the positive patients using nanopore sequencing technology in country, and assessed the circulating genotypes, prevalence of drug and antibody resistance markers. We found overwhelmingly that genotype E variants are in circulation, while we also observed a wide range of drug and vaccine resistance phenotypes, which is concerning considering the lack of treatment options within the country. This study demonstrates the utility of nanopore sequencing in the field, while also highlighting the problem of HBV in Sierra Leone.
Dr. Luke Meredith is a post-doctoral research fellow based at the University of Cambridge, working with Prof. Ian Goodfellow. Obtaining a PhD in Molecular Virology in 2009, Dr. Meredith's post-doctoral work focused on virus binding and entry. In 2015, he joined the West African Ebola outbreak response and spent 7 months in Sierra Leone, initially as part of the Public Health England diagnostic response, then subsequently as part of the clinical research team evaluating diagnostic tests. He then spent a further 3 months running the Ebola Outbreak Sequencing Service, providing real-time sequencing support to the response, enabling the rapid characterisation of EVD cases during the latter stages of the epidemic. Following the epidemic, Dr. Meredith played a key role in the establishment of the University of Makeni Infectious Disease Research Laboratory, a legacy teaching and research laboratory which provides training to Sierra Leonean graduate students, as well as being the base for research and surveillance projects monitoring the diversity and prevalence of infectious disease in Sierra Leone and surrounding countries in West Africa.
Bacterial species level identification and strain level differentiation using repetitive extragenic palindromic based amplicon sequencing with Oxford Nanopore Technology
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University of Copenhagen/GenXone
We have developed a new method for fast and cost-effective bacterial species level identification and strain level differentiation using Repetitive Extragenic Palindromic based amplicon sequencing on MinION platform. The method utilizes an optimized version of rep-PCR followed by dual-stage rep-PCR-2, during which sample specific barcodes are incorporated. DNA enrichment together with barcoding takes less than 5 hours and ensures highly repetitive and evenly distributed reads per sample. Our results demonstrate that sequencing of the rep-PCR genomic fingerprint profile with Oxford Nanopore Technology generates highly reproducible peak profiles. We have developed a pipeline that, by correcting the random error of individual reads within each peak, generates a set (~10 reads per sample; 300bp - 3Kb) of high quality (>99%) consensus reads. The information from high quality reads is used to retrieve species level identification. Furthermore, we have developed an algorithm that compares integrals of the peaks profiles allowing for strain level discrimination.
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Lukasz Krych completed his PhD in Food Microbiology in 2014 at the University of Copenhagen, where he is now a post-doctoral researcher. He utilises molecular genetics and classical microbiological techniques to investigate the association of the gut microbiome with health and disease. This involves the development of novel data analysis tools, multivariate data mining and protocol optimisation. Lukasz is also R&D director at GenXone, a Polish biotech company specialising in the development of diagnostic products based on the latest DNA testing technologies.
Carika Weldon
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DeMontfort University, UK
Dr Carika Weldon is a lecturer in Biomedical Science at De Montfort University in Leicester. Prior to joining the faculty as the youngest lecturer in the university’s history, she obtained her BSc (Hons) Medical Biochemistry in 2011 and her PhD in Biochemistry in 2015 from the University of Leicester.
Dr Weldon’s doctoral work focused on alternative splicing of the apoptotic gene Bcl-X. By creating the new FOLDeR method, she discovered that G-quadruplexes shifts the XS/XL ratio to favour the pro-apoptotic XS isoform. By screening over 30 G-quadruplex ligands, her work identified a suitable drug that could be used for treating cancers, based on its ability to shift the ratio almost 40-fold. In her own lab now she looks at how the presence of G-quadruplexes in pre-mRNA can influence alternative splicing in other genes. She is utilizing the versatile technique of nanopore technology to detect modified guanine with the hopes of gaining more insight into the exciting fields of splicing and G-quadruplexes.
Recent publications
Weldon, C. et al. Specific G-quadruplex ligands modulate the alternative splicing of Bcl-X. Nucleic Acids Research (2017). doi:10.1093/nar/gkx1122
Weldon, C. et al. Identification of G-quadruplexes in long functional RNAs using 7-deazaguanine RNA. Nature Chemical Biology 13, 18–20 (2017).
Cas9 targeted enrichment for nanopore profiling of methylation at known cancer drivers
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Johns Hopkins University
CpG methylation in the mammalian genome is known to alter the binding of transcriptional regulatory factors, and through this activity mediate changes in chromatin structure and gene expression. We have previously shown the ability to call the methylation status of CpG sites using the signal from nanopore sequencing, and we are aiming to leverage this to profile the methylation status at high sequencing depth of genes known to be involved in tumorigenesis. These efforts have focused on using Cas9-enrichment, sidestepping the relatively high cost/bp of nanopore sequencing while retaining its exquisite sensitivity and long-reads. This allows us to profile signals of methylation over a long range on a single DNA molecule, and by comparing cells with different malignant potential, we can provide new insight into the dynamics of CpG methylation patterns. Specifically, we have targeted the promoter region of the human telomerase gene (hTERT), which is known to have altered methylation patterns that reflect the malignant potential of different cell line. This region is typically difficult to profile with bisulfite amplicon sequencing because of the repetitive and high CG density. Using thyroid cancer cell lines, we have sequenced this region, and identified both methylation level and individual single-read methylation patterns in the samples.
Timothy Gilpatrick is a current MD/PhD student at Johns Hopkins University working in the lab of Winston Timp to leverage sequencing technologies for insight into epigenetic states and transcriptional regulation. He received his BSc in Biochemistry from the University of Delaware, where he worked on characterizing the role of lipoprotein-associated enzymes in atherosclerosis. Prior to starting his graduate studies, he worked as a research fellow at the National Institutes of Health, where his work centered on understanding how microRNAs regulate epigenetic silencing machinery in mouse ES cells. He hopes to marry his interests in medicine and genomics to work in the development and application of sequencing-based diagnostic techniques. When not in lab, Timothy enjoys city biking, yoga, and music production.
Cassava Virus Action Project
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Cassava Virus Action Project
Approximately 800 million people rely on cassava globally, either as a source of food or a source of income. But cassava is being devastated by two viruses, both transmitted by the whitefly: Cassava mosaic disease and Cassava brown streak disease. The Cassava Virus Action Project (www.cassavavirusactionproject.com) is a network of researchers, farmers and others, collaborating to use genomic technologies to improve the management of these cassava viruses. DNA analysis of the virus, quickly and close to the crop, can help farmers to decide what action to take. We have empowered local communities to take decisions that maximize their crops while also minimizing the spread of these whitefly-borne viruses. For the first time, farmers struggling with diseased cassava crops can take immediate, positive action to save their livelihoods based on information about the health of their plants generated using a portable, real-time DNA analysis device. The project aims to reduce the risk of community crop failure and help preserve livelihoods. Oxford Nanopore Technologies portable MinION was used to identify which strain of virus was destroying the cassava crops of farmers in Tanzania and Uganda as part of the Cassava Virus Action Project. As the MinION delivers the information in real time (compared to the usual three months), farmers were able to take action much faster. For example, one was advised to destroy the crop and plant a different variety that is more resistant to the virus. In this talk I will outline how our team is using supercomputing, genomics, mobile DNA sequencing technology and teamwork to impact the lives of millions. The team’s latest work to bring portable DNA sequencing to east African farmers has been featured on CNN, BBC World News, BBC Swahili, BBC Technology News, and the TED Fellows Ideas Blog.
Dr. Laura Boykin is a TED Senior Fellow (2017), Gifted Citizen (2017) and a computational biologist who uses genomics and supercomputing to help smallholder farmers in sub-Saharan Africa control whiteflies, which have caused devastation of local cassava crops. Her lab at The University of Western Australia uses genetic data to understand the virus and whitefly’s evolution. Boykin also works to equip African scientists with a greater knowledge of genomics and high-performance computing skills to tackle future insect outbreaks. Boykin completed her PhD in Biology at the University of New Mexico while working at Los Alamos National Laboratory in the Theoretical Biology and Biophysics group, and is currently a Senior Research Fellow at University of Western Australia. She was invited to present her lab’s research on whiteflies at the United Nations Solution Summit in New York City for the signing of the Sustainable Development Goals to end extreme poverty by 2030. The team’s latest work to bring portable DNA sequencing to east African farmers has been featured on CNN, BBC World News, BBC Swahili, BBC Technology News, and the TED Fellows Ideas Blog.
Dr. Joseph Ndunguru is the head of the Mikocheni Agricultural Research Institute in Tanzania and principle investigator of several research projects. These include being the regional coordinator of Disease Diagnostics for Sustainable Cassava Productivity in Africa, co-funded by the Bill & Melinda Gates Foundation and DFID, a project implemented in Tanzania, Kenya, Uganda, Rwanda, Malawi, Mozambique and Zambia. In September 2012, Joseph received a Presidential medal award on Scientific Discoveries and Research Excellence, and an award for the best National Agricultural Research Scientist for 2011. He is an Adjunct Professor at the Nelson Mandela African Institute of Science and Technology and is also the National Biotechnology Research Coordinator in Tanzania. His research interest is to understand plant viruses at the molecular level, their genome organization, gene expression and to develop resistance to plant viruses of economic importance to Africa. Cassava mosaic geminiviruses, cassava brown streak virus and sweet potato viruses are his main focus for now.
Dr. Titus Alicai is a plant virologist and Principal Research Officer and programme leader of Root Crops Research at the National Agricultural Research Organisation National Crops Resources Research Institute in Kampala Uganda. He is currently leading a team of 150 staff including 7 PhD and 9 MSc students. Dr. Alicai’s formal education includes a PhD in Plant Virology from the Natural Resources Institute at the University of Greenwich in the U.K and MSc and BSc in Agriculture from Makerere University, Kampala, Uganda. His groundbreaking research on cassava viruses is internationally recognized and has been published in journals such as PNAS and Plant Pathology. His leadership and research excellence has led to securing over 5 million dollars in grant funding for continued support of his cassava virus research from organizations such as USAID and the Bill and Melinda Gates Foundation.
Recent publications
Ateka, E. et al. Unusual occurrence of a DAG motif in the Ipomovirus Cassava brown streak virus and implications for its vector transmission. PLoS ONE 12, (2017).
Chiron basecaller
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University of Queensland, Australia
Chiron is a tool for segmentation-free base-calling, using deep learning. Researchers can either use pre-trained models, or can use Chiron to learn new models.
Lachlan completed a Bachelor of Science at Australian National University, majoring in Mathematics. After several years out of science working in consulting, he went to the Wellcome Trust Sanger Institute, UK to complete a PhD in bioinformatics. Lachlan was a research fellow at the School of Public Health, Imperial College London, largely working on methodology for genome-wide association studies. He returned to Australia in 2012 to start a group at the Institute for Molecular Bioscience, University of Queensland where his group works on developing genomics and bioinformatics tools in infectious disease and cancer.
Clinical applications for real-time sequencing in leukaemia
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Fred Hutchinson Cancer Research Center, USA
Leukemias are characterized by a variety of distinct cytogenetic and molecular subgroups that impact response and survival. Many of these leukemias have specific translocations and mutations that confirm the suspected diagnosis, provide prognostic information, and guide therapy. A particular challenge in current molecular pathology practice is the high cost and long turnaround times for reporting of molecular profiles in these leukemias. Our research aims to use real-time sequencing for more efficient and improved molecular diagnostics workflows. Our work involves development of a real-time sequencing assay for detection of fusion genes and to sequence the FLT3 gene transcript to detect mutations in leukemias using the MinION platform.
Dr. Cecilia Yeung is an Associate Member at the Fred Hutchinson Cancer Research Center where she serves as the medical director of the Molecular Oncology Laboratory. She is an Assistant Professor at the University of Washington, Department of Anatomic Pathology where she serves as the chair of the Clinical Competency Committee for the Molecular Genetics Pathology Fellowship, and the director for the Molecular Pathology Elective. She is the co-coordinator and speaker of the Molecular Pathology Lecture Series for residents and fellows. She is a member of the Board of Directors and the chair of the Teaching and Education Committee at the Association for Molecular Pathology. Her clinical appointment at Seattle Cancer Care Alliance is where she focuses her pathology diagnostic skills in immunotherapy, transplant, and hematopathology. Her research interest focuses on developing novel molecular diagnostics for hematologic malignancies, and improving correlative data from clinical trials via implementation of better translational medicine diagnostic assays.
Dr. Olga Sala Torra is a staff scientist in the Radich laboratory at the Fred Hutchinson Cancer Research Center in Seattle, WA. Her main research interests are the application of gene expression and sequencing techniques to the detection of minimal residual disease in leukemias, and the development of low-cost diagnostic methods for hematologic malignancies that can be useful in low-income countries.
Recent publications
Sala Torra, O. et al. Next-Generation Sequencing in Adult B cell Acute Lymphoblastic Leukemia Patients. Biology of Blood and Marrow Transplantation 23, 691–696 (2017).
Torra, O. S., Beppu, L., Smith, J. L., Welden, L., Georgievski, J., Gupta, K. Radich, J. P. (2016, June 2). Paper or plastic? BCR-ABL1 quantitation and mutation detection from dried blood spots. Blood. American Society of Hematology. https://doi.org/10.1182/blood-2015-12-689059
Clive Brown: Plenary from London Calling 2018
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Oxford Nanopore Technologies
Clive is Chief Technology Officer at Oxford Nanopore Technologies. On the Executive team, he is responsible for all of the Company’s product-development activities. Clive leads the specification and design of the Company’s nanopore-based sensing platform, including strand DNA/RNA sequencing and protein-sensing applications with a strong focus on scientific excellence and successful adoption by the scientific community.
Clive joined Oxford Nanopore Technologies from the Wellcome Trust Sanger Institute (Cambridge, UK) where he played a key role in the adoption and exploitation of next-generation DNA sequencing platforms. This involved helping to set up the world’s largest single installation of Illumina (formerly Solexa) Genome Analyzers in a production sequencing environment, initially used to pioneer the 1000 Genomes Project.
From early 2003 he was Director of Computational Biology and IT at Solexa Ltd, where he was central to the development and commercialisation of the Genome Analyzer (GA). Solexa was sold to Illumina for $650m in early 2007 after the successful placement and adoption of 12 instruments. The Solexa technology, now commercialised by Illumina, is the market-leading DNA sequencing technology driving the renaissance in DNA-based discovery.
He has a strong background in computer science and genetics/molecular biology and manages interdisciplinary teams including mechanical engineering, electronics, physics, surface chemistry, electrophysiology, software engineering and applications (of the technology). Clive applies modern agile management techniques to the entire product-development lifecycle.
Clive has also held various management and consulting positions at GlaxoWellcome, Oxford Glycosciences and other EU- and US-based organisations. He has worked at the interface between computing and science, ranging from genetics to proteomics. He holds degrees in Genetics and Computational Biology from the University of York.
Complex structural variants resolved by short-read and long-read whole genome sequencing in Mendelian disorders
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University of Cambridge
Complex structural variants (cxSVs) are genomic rearrangements comprising multiple structural variants, typically involving three or more breakpoint junctions. They contribute to human genomic variation and can cause Mendelian disease, however they are not typically considered during genetic testing. We investigated the role of cxSVs in Mendelian disease using short-read whole genome sequencing (WGS) data from 1,324 individuals with neurodevelopmental or retinal disorders from the NIHR BioResource project. We identified four cases of individuals with a cxSV affecting Mendelian disease-associated genes. We used nanopore sequencing to resolve the mechanism of one of the variants. Our results show cxSVs are an important, although rare cause of Mendelian disease, and we therefore recommend their consideration during research and clinical investigations.
Alba Sanchis-Juan studied Biochemistry and Biomedicine at University of Valencia, Spain. She is a PhD student and works at the Department of Haematology, University of Cambridge. Her study has been focused on the use of next-generation sequencing for clinical research and diagnosis. Currently, she performs data analysis of whole genome sequence data of individuals with neurodevelopmental disorders.
Recent publications
Sanchis-Juan, A. et al. Complex structural variants resolved by short-read and long-read whole genome sequencing in Mendelian disorders. bioRxiv 281683 (2018). doi:10.1101/281683
Coral holobionte species identification onboard Tara with MinION sequencing of multiple barcodes.
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Genoscope - Centre National de Séquençage
Molecular identification of species has long been possible via marker gene sequencing but requires bulky instruments and controlled laboratory conditions which are impractical for environmental experiments in isolated places. Recent advances in sequencing technologies now permit rapid in situ sequencing, but development of specific protocol pipelines from DNA extraction to bio-informatic analyses is still required for efficient sample processing. Here, we chose a combination of 3 marker genes in order to identify 85 different coral colonies and their holobionte onboard the research vessel Tara. We developed specific protocols for DNA extraction and multi-PCR amplifications in order to process a large number of samples in a restricted space and time. We used Oxford Nanopore Technologies to sequence amplicons on a MinION device and developed bioinformatics pipelines to analyze nanopore reads on a simple laptop, obtaining results in less than 36 hours. Protocols and tools used in this work may be applicable at a larger scale for rapid environmental diagnosis of complex samples in the context of climate change.
Quentin Carradec received his PhD in genetics and molecular biology from Pierre and Marie Curie University in Paris in 2014. He currently works on environmental genomics at Genoscope Institute, France in Patrick Wincker’s research group. His research focuses on the diversity and activity of marine planktonic species with the analysis of metagenomic and metatranscriptomic sequencing data in the framework of Tara expedition projects. He recently joined the Tara Pacific project to study resistance and adaptation of coral holobionte to environmental change.
De novo sequencing and assembly of plant genomes using nanopore long reads
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Genoscope - Centre National de Séquençage
Plant genomes are often characterized by their high level of repetitiveness and polyploid nature. As a direct consequence, genome assemblies of plant genomes are challenging. The introduction of short-reads technologies ten years ago, significantly increased the number of available plant genomes. Generally, these assemblies are incomplete and fragmented, and only a few of them are at the chromosome-scale. Recently, Oxford Nanopore sequencing technology was commercialized with the promise to sequence long DNA fragments (kilobases to megabases order) and then, by using efficient algorithms, provide assembly of high quality in terms of contiguity and completeness of the repetitive regions. Here we describe the de novo sequencing and assembly of several plant genomes (banana, citrus and brassicaceae) and the impact of read length on the contiguity and completion of genome assemblies.
Jean-Marc Aury is a researcher at Genoscope since 2003. He was focused on eukaryotic genome analysis and was a main actor of several genome projects, like paramecium, grape, banana, cocoa and oak. He is now the team leader of a bioinformatic group which is focused on sequencing data production, genome assembly and gene prediction in eukaryotic genomes, with a broad interest in methodological development. Genoscope acts as the French National Sequencing Centre since 1998 and has an extensive experience in large sequencing projects (for example the Tara Oceans metagenomic project). Genoscope has participated in the MinION and PromethION Early Access Program.
Recent publications
Istace, B. et al. de novo assembly and population genomic survey of natural yeast isolates with the Oxford Nanopore MinION sequencer. GigaScience 6, (2017).
Schmidt, M. H. et al. de novo assembly of a new Solanum pennellii accession using nanopore sequencing. The Plant Cell tpc.00521.2017 (2017). doi:10.1105/tpc.17.00521
Carradec, Q. et al. A global ocean atlas of eukaryotic genes. Nature Communications 9,(2018).
Madoui, M. A. et al. Genome assembly using nanopore-guided long and error-free DNA reads. BMC Genomics 16, (2015).
Detecting DNA modifications and structural variants from nanopore long-read sequencing data
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Children’s Hospital of Philadelphia
Compared to short-read sequencing techniques, Oxford Nanopore Technologies long-read sequencing platform has several advantages, such as the ability to detect DNA modifications directly from electric signals, and the improved sensitivity to find structural variants. Here we describe a novel method called NanoMod to improve the performance of detecting DNA modifications, especially synthetically introduced modifications, by analyzing the characteristics of raw signal intensities. We also describe a data handling pipeline for detecting structural variants from long-read data. We illustrate a few examples of pinpointing the exact breakpoints of balanced translocations or identifying causal structural variants in exome-negative patients, which subsequently enabled pre-implementation genetic diagnosis.
Dr. Kai Wang is an Associate Professor at the Raymond G. Perelman Center for Cellular and Molecular Therapeutics of the Children’s Hospital of Philadelphia, and Department of Pathology & Laboratory Medicine at the University of Pennsylvania’s Perelman School of Medicine. He received a Bachelor’s degree from Peking University in China, a master’s degree from the Mayo Clinic, and a PhD from the University of Washington. He had postdoctoral training at the University of Pennsylvania and the Children’s Hospital of Philadelphia, before becoming an Assistant Professor, and later Associate Professor at the University of Southern California Keck school of Medicine, and then Columbia University Medical Center. His research focuses on the development and application of genomic approaches to study the genetic basis of human diseases and facilitate the implementation of genomic medicine.
Recent publications
Liu, Q., Georgieva, D. C., Egli, D. & Wang, K. NanoMod: a computational tool to detect DNA modifications using nanopore long-read sequencing data. bioRxiv 277178 (2018). doi:10.1101/277178
Detection of clinically relevant molecular alterations in CLL by nanopore sequencing
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University of Oxford, UK
Chronic Lymphocytic Leukaemia (CLL) is the most common form of leukaemia in the Western world, and is characterised by both clinical and biological heterogeneity. The majority of CLL patients display few symptoms at diagnosis, after which the disease can progress into either an aggressive, chemo-resistant form with poor prognosis, or a relatively indolent form with a life expectancy similar to that seen in the normal population. The path taken by any particular CLL case is influenced by the presence or absence of a number of specific molecular alterations, including copy number changes such as trisomy 12, del(11q), del(13q) and del(17p), the mutational status of the immunoglobulin heavy chain (IgHV), and the presence of somatic mutations within TP53. As such, identification of these changes is an important part of the treatment decision process. Here I will highlight our work using a combination of targeted and ultra-low coverage whole genome sequencing on the MinION platform, to simplify the detection of these clinically important molecular alterations in CLL.
Dr Adam Burns is a post-doctoral researcher in the Oxford Molecular Diagnostics Centre based in the Department of Oncology at the University of Oxford. His research focuses on developing next-generation sequencing-based tools for clinical diagnostic use. After obtaining his BSc from the University of Hull, Adam worked in industry for five years before joining Oxford University in 2009. There he developed screening assays for clinically relevant mutations, including KRAS, BRAF and JAK2, across a range of haematological malignancies. As part of his PhD from Oxford Brookes University in 2016, Adam developed targeted and whole genome sequencing approaches to help diagnose haematological malignancies. This work was subsequently adopted for routine diagnostic use in the Oxford University Hospitals NHS Foundation Trust and also informed the Genomics England 100,000 Genomes Project. Adam’s current research is centred on using nanopore sequencing, and other patient-near technologies, as an accurate, low-cost, easy-to-use screening platform to detect clinically relevant genetic changes in haematological malignancies for use in resource-poor regions of the world.
Recent publications
Burns, A. et al. Whole-genome sequencing of chronic lymphocytic leukaemia reveals distinct differences in the mutational landscape between IgHVmut and IgHVunmut subgroups. Leukemia 32, 332–342 (2018)
Stamatopoulos B, et al. Targeted deep sequencing reveals clinically relevant subclonal IgHV rearrangements in chronic lymphocytic leukemia. Leukemia 31, 837–845 (2017)
Pellagatti, A. et al. Targeted resequencing analysis of 31 genes commonly mutated in myeloid disorders in serial samples from myelodysplastic syndrome patients showing disease progression. Leukemia 30, 247–250 (2016)
Detection of GBA missense mutations and other variants using the Oxford Nanopore MinION
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UCL Institute of Neurology
Mutations in GBA cause Gaucher disease when biallelic, and are strong risk factors for Parkinson’s disease when heterozygous. GBA analysis is complicated by the presence of a nearby pseudogene. Here we present a method for sequencing GBA, using an amplicon including all coding regions and introns, on the Oxford Nanopore MinION, enabling a fast and comprehensive assessment. For illustration we successfully sequenced DNA samples from 17 individuals, including patients with Parkinson’s and Gaucher disease, in a study combining earlier and current nanopore chemistry. We initially compared different aligners (Graphmap and NGMLR), and used Nanopolish and Sniffles to call variants, and NanoOK for quality metrics. Many samples had previously known mutations, including the common p.N409S (N370S) and p.L483P (L444P). We detected these, mostly in a blinded fashion, and other causative mutations in Gaucher patients. In a sample with the complex RecNciI allele, we detected an additional coding SNP, and a 55-base pair deletion in data aligned by NGMLR. We haplotyped all samples using Whatshap and confirmed compound heterozygosity where relevant. False positives were fewer with NGMLR, and easily identified and filtered. We demonstrate the potential of the MinION to analyse this difficult gene, with the added advantage of phasing and intronic analysis.
Christos Proukakis is a clinical academic neurologist, holding a senior lectureship at UCL Institute of Neurology and is an honorary consultant neurologist at the Royal Free NHS Trust. His work focuses on Parkinson’s disease, investigating the role of somatic mutations and the utility of new sequencing technologies.
Recent publications
Nacheva, E. et al. DNA isolation protocol effects on nuclear DNA analysis by microarrays, droplet digital PCR, and whole genome sequencing, and on mitochondrial DNA copy number estimation. PLoS ONE 12, (2017)
Kara, E. et al. Genetic and phenotypic characterization of complex hereditary spastic paraplegia. Brain 139: 1904-18, (2016)
Kiely, AP. et al. Distinct clinical and neuropathological features of G51D SNCA mutation cases compared with SNCA duplication and H50Q mutation. Mol Neurodegener,10:41, (2015)
Porcari, R. et al. The H50Q mutation induces a 10-fold decrease in the solubility of α-synuclein. Journal of Biological Chemistry 290, 2395–2404 (2015)
Beavan, M. et al. Evolution of prodromal clinical markers of parkinson disease in a GBA mutation-positive cohort. JAMA Neurology 72, 201–208 (2015).
Determining novel antimicrobial resistance mechanisms with Oxford Nanopore long-read sequencing data
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University of Texas Health Science Center at Houston, USA
Next-generation sequencing technology has revolutionized the study of microbial genomics and has the potential to enable near real-time pathogen identification and antimicrobial resistance pattern prediction in clinical settings. The use of traditional short-read sequencing has limitations, as it is difficult to resolve repeats, multiple replicons, and other complex antimicrobial resistance mechanisms in the analysis of single bacterial genomes. The use of Oxford Nanopore sequencing overcomes these limitations, allowing us to leverage ultra-long reads to resolve these complex resistance mechanisms and identify new and novel ones as well. I will present the work our lab is conducting to elucidate complex resistance mechanisms, including a large tandem duplication of a b-lactamase encoding transposon in an Escherichia coli plasmid, the duplication of a KPC-3 encoding transposon within a large plasmid in Klebsiella pneumoniae, and the resolution of a transposon in a pair of Pseudomonas aeruginosa isolates, all of which provide resistance to antibiotics commonly used to treat infections caused by these bacteria. I will also discuss what our lab is doing to screen for more of these complex resistance mechanisms, with the goal of expanding our understanding of the full repertoire of mechanisms utilized by bacteria, and bringing us closer to near real-time prediction of antimicrobial resistance in clinical settings.
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Dr. Hanson is currently an Assistant Professor in the Department of Epidemiology, Human Genetics and Environmental Sciences in the School of Public Health, and the Department of Internal Medicine, Division of Infectious Diseases. He also serves as the Associate Director of Microbial Genomics in the Center for Antimicrobial Resistance and Microbial Genomics (CARMiG) at the McGovern Medical School.
Dr. Hanson’s research interests are in infectious disease transmission and colonization, how microbial communities impact the development of disease, and how antimicrobial resistance develops and transmits through society. He uses a combination of existing and innovative laboratory techniques, as well as cutting-edge sequencing and bioinformatics within his lab’s research.
Devon O'Rourke
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University of New Hampshire
Devon O'Rourke is a PhD candidate at the University of New Hampshire and co-advised by Dr. Matt MacManes and Dr. Jeffrey Foster. He uses nanopore in his day job investigating functional genomics of disease resistance in North American bats. He uses nanopore just for fun, conducting metagenomic experiments within high school and college classes with the goal of doing cool science anytime, anywhere, by anyone, on any budget.
Evaluating the extensively drug-resistant Klebsiella pneumoniae resistome via MinION direct RNA sequencing
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University of Queensland, Australia
Klebsiella pneumoniae is one of the leading causes of nosocomial infections, frequently possesses multidrug resistance and subsequently results in high mortality. The DNA and RNA of extensively drug-resistant (XDR) K. pneumoniae clinical isolates (Hygeia General Hospital, Greece) were sequenced in this study. MinION sequencing was utilised to assemble these genomes, discern the differential expression of antibiotic resistance genes and ascertain the time required for detection. DNA sequencing identified the majority of acquired resistance (≥75%) resided on plasmids and detected ≥70% of these genes within 2 hours. Direct RNA sequencing successfully revealed aminoglycoside, beta-lactam, trimethoprim and sulphonamide resistance within 2 hours. Resistance towards other antibiotic classes was detected; however, this was dependent on the level of expression which was further validated via qRT-PCR. MinION sequencing was capable of detecting antibiotic resistance in these XDR K. pneumoniae isolates within hours and differential gene expression was successfully discerned via direct RNA sequencing.
Miranda Pitt completed her undergraduate studies at The University of Queensland, Australia. Courses selected in her Bachelor of Biomedical Science degree predominantly focused on infectious disease, immunology and genetics. In 2013, she commenced an Honours degree at the University of Queensland Diamantina Institute, where she investigated differential gene expression in an ankylosing spondylitis mouse model and received an Honours Class I. She is currently a PhD student at the Institute for Molecular Bioscience at The University of Queensland. Her research delves into understanding the mode of action of last resort antibiotics against multidrug-resistant gram-negative bacteria and the genetic basis underpinning resistance.
Recent publications
Pitt, ME. et al. Multifactorial chromosomal variants regulate polymyxin resistance in extensively drug-resistant Klebsiella pneumoniae. Microb Genom (ahead of print) (2018) doi: 10.1099/mgen.0.000158.
Evaluation of nanopore sequencing for bacterial biothreat pathogens
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Centers for Disease Control and Prevention
In the event of a deliberate release of a bacterial biothreat agent, rapid characterization of the implicated strain(s) will be critical to the public health response. High quality, whole genome sequencing (WGS) can rapidly reveal genetic engineering, such as the introduction of antimicrobial resistance factors and/or plasmids. Laboratory work with these bacterial pathogens often occurs in space-limited, high containment facilities. On-site nanopore sequencing that produces rapid WGS data with real-time analysis capabilities may reduce the time to results during a public health emergency. Here we present an evaluation of DNA isolation methods and the performance of rapid sequencing library preparation methods for Bacillus anthracis and Yersinia pestis to determine (1) DNA quantity and quality, (2) if the purified DNA can be used for rapid library preparation, (3) the sequence quality of MinION versus Illumina and PacBio data, and (4) whether known antimicrobial resistance markers and plasmids can be identified.
Amy Gargis is a microbiologist at the U.S. Centers for Disease Control and Prevention (CDC), Atlanta. Dr. Gargis earned her M.S. and Ph.D. in Microbiology from The University of Alabama. After receiving her Ph.D. in 2010, she joined the Division of Laboratory Systems at the CDC, where she focused on efforts to improve the quality of genetic testing in the clinical and public health laboratory setting. Dr. Gargis was co-lead in organizing two national workgroups of experts to review and establish consensus guidelines for scientific principles, clinical laboratory practices, regulatory requirements, and professional standards for next-generation sequencing. In 2014, Dr. Gargis joined the BioDefense Research and Development Laboratory within the Division of Preparedness and Emerging Infections at the CDC. In this position, she works to develop and optimize rapid assays to characterize biological threat agents, with an emphasis on detection of antibiotic resistance.
Recent publications
Gargis, A. S., Kalman, L. & Lubin, I. M. Assuring the quality of next-generation sequencing in clinical microbiology and public health laboratories. Journal of Clinical Microbiology 54, (2016)
Gargis, A. S. et al. Good laboratory practice for clinical next-generation sequencing informatics pipelines. Nature Biotechnology 33, 689–693 (2015)
Gargis, a S. et al. Assuring the quality of next-generation sequencing in clinical laboratory practice. Nature Biotechnology 30, 1033–1036 (2012)
Genome assembly in Drosophila using nanopore
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Stowers Institute for Medical Research
The Drosophila genus is a highly-studied group in which many species possess a well-developed set of genetic tools, and for which high-quality genome assemblies are available. This has facilitated studies of function and evolution of cis-regulatory regions and proteins by allowing comparisons across at least 50 million of years of evolution. Yet, there remains substantial genetic diversity within the Drosophila genus that available genomes fail to capture. We asked if Oxford Nanopore technology could be used to rapidly and inexpensively sequence and assemble the genome from any Drosophila species. This technology allowed us to generate high-quality genome assemblies of 16 Drosophila species, including from 11 of the 12 originally sequenced Drosophila species. Alignment of contigs from the published reference genomes to our assemblies demonstrated that approximately 60% of gaps present in currently published reference genomes could be closed using this technology. Importantly, we were able to show that Drosophila assemblies could be generated for approximately $1,000 (USD), providing a roadmap for the affordable sequencing and assembly of additional Drosophila genomes.
Danny Miller received both an MD and PhD from the University of Kansas and completed his PhD work in the laboratory of Scott Hawley at the Stowers Institute for Medical Research. He has always been interested in sequencing more species of Drosophila and understanding structural variation within the melanogaster species group and jumped at the chance to sequence and assemble multiple Drosophila genomes using nanopore technology. He will begin a combined residency in Pediatrics and Medical Genetics at the University of Washington and Seattle Children’s Hospital in June 2018.
Recent publications
Miller, D. E., Staber, C., Zeitlinger, J., & Hawley, R. S. (2018). High-quality genome assemblies of 15 Drosophila species generated using Nanopore sequencing. BioRxiv, 8601, 267393. https://doi.org/10.1101/267393
Solares, E. A., Chakraborty, M., Miller, D. E., Kalsow, S., Hall, K. E., Perera, A. G. Hawley, R. S. (2018). Rapid low-cost assembly of the Drosophila melanogaster reference genome using low-coverage, long-read sequencing. BioRxiv, 267401. https://doi.org/10.1101/267401
Haplotyping of key cardiac disease genes using long-read sequencing
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Stanford University
Hypertrophic cardiomyopathy, characterized by an overgrowth of the left ventricular heart wall, affects 1:500 in the population and can lead to atrial fibrillation, heart failure, and sudden death. Causative genetic mutations identified in sequenced patients most often occur in one of two genes: MYH7 (myosin heavy chain 7) or MYBPC3 (cardiac myosin binding protein c), key components of the cardiac sarcomere. Here, we use targeted long-read sequencing to connect rare genetic variants in sarcomeric genes to novel RNA isoforms. We additionally use long-read sequencing to haplotype cardiac-disease associated genes to identify targets for precision medicine therapeutics. Targeted, multiplexed long-read sequencing of key cardiac disease genes presents an efficient strategy for defining precision medicine targets and providing evidence for disease-causing mutations in cardiovascular disease.
Alex is a PhD candidate in Euan Ashley's lab at Stanford University, studying hypertrophic cardiomyopathy. Her thesis research involves sequencing and haplotyping clinically relevant genes in cardiac disease and using that information to design allele-specific, precision therapeutics.
Recent publications
Dainis, A.M. Cardiovascular precision medicine in the genomics era. JACC: Basic to Translational Science, 3, 313-326 (2018)
High Coverage, Ultra-long Read Sequencing
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How MinION sequencing is helping us solve real-life environmental biotechnology issues
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Orvion B.V.
I will be talking about two cases whereby MinION sequencing has provided the insight we need to take environmental biotechnology a step further: Firstly, a landfill is leaching the pesticide Mecoprop into the groundwater. No degradation occurs naturally and the pesticide is therefore gradually spreading. We performed degradation tests and MinION sequencing to identify which bacteria are able to degrade Mecoprop. This information will be used to perform a pilot bioremediation project on-site to remove the pollutant from the groundwater altogether. Secondly, wastewater treatment plants (WWTP) form a crucial barrier between human activities and the environment. Micro-organisms are, for the main part, responsible for degrading hazardous compounds in wastewater, yet very little is known about these wastewater workhorses and how they might be optimised. We are screening the microbiology present in different WWTP’s, together with an industrial water company, to determine the microbial baseline in their treatment plants and which microbial indicators provide early warning that they are not performing optimally. In the longer term this data will be used to determine how wastewater treatment processes can be made more effective.
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Aleida is a molecular microbiologist who has been working within the field of environmental and industrial microbiology since 2006 after she graduated from the University of Groningen in the Netherlands. She has always been involved in making complex microbial processes more visible and tangible, for clients and/or own research, through monitoring and measuring using molecular microbial methods e.g. for biological soil remediation, water treatment and biocorrosion. Since May 2016 her company Orvion has started to work with the MinION to provide fast, flexible and in-depth insight into the microbial processes they work with (or against…).
Human genome sequencing on PromethION
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Human genome sequencing on PromethION to investigate tandem repeats in dementia
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University of Antwerp
Expanded DNA tandem repeats can cause disease through their length, repeat unit sequence, and nucleotide modifications. However, these features are often difficult, if not impossible, to assess. We aim to tackle these issues with long-read human whole genome sequencing on PromethION. Starting with biomaterials obtained from dementia patients carrying C9orf72 repeat expansions (the most common cause of FTLD/ALS) or ABCA7 VNTR repeat expansions (a recently identified risk factor for Alzheimer’s disease), we consistently generate more than 90 Gigabase (> 25X human genome coverage) per sample on a single PromethION flow cell. First, we are evaluating whether the acquired long-sequencing reads can accurately measure repeat length. Secondly, we are looking into sequence differences and nucleotide modifications, and their relation to dementia. With this work, we aim to improve our understanding of repeat expansions in dementia and enable in-depth and high-throughput analysis of tandem repeats on a genome-wide scale.
Arne De Roeck is a PhD student in the Neurodegenerative Brain Diseases Group at the Center for Molecular Neurology (CMN), VIB – University of Antwerp, led by Prof. dr. Christine Van Broeckhoven. CMN has several decades of expertise in genetics of dementia and has been part of the Oxford Nanopore Technologies adventure from the beginning. In 2018, CMN sequenced several human whole genomes on PromethION, achieving some of the first and highest yield sequencing runs in the field.
Improving MinION read accuracy to enable the high-throughput analysis of single cell transcriptomes.
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University of California, Santa Cruz
We have previously shown that Oxford Nanopore Technologies cDNA sequencing can uncover transcript isoform diversity in single cells in unprecedented detail. Now, we have developed a new method to increase the accuracy of cDNA reads generated by the Oxford Nanopore Technologies MinION. These more accurate reads can be used to demultiplex high-throughput single cell cDNA libraries and identify base-accurate full-length transcript isoforms. We have benchmarked our new method by analyzing a cDNA pool of 96 B cells and found isoform diversity with potential implications for cancer treatment.
Chris Vollmers graduated with a M.S. in Biomedical Sciences from the University of Wuerzburg in Germany before pursuing a Ph.D. through a shared program between the University of Heidelberg in Germany and the Salk Institute for Biological Studies in La Jolla, California. He then joined the lab of Stephen Quake at Stanford University as a postdoctoral fellow and worked on developing genomic tools to analyze B cells on population and single cell levels. He now continues this work in his own lab in the Biomolecular Engineering Department at UCSC since 2014.
Recent publications
Byrne, A. et al. Nanopore long-read RNAseq reveals widespread transcriptional variation among the surface receptors of individual B cells. Nature Communications 8, (2017)
Insights into vancomycin-resistant enterococci outbreaks through short- and long-read sequencing
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Interactive exploration of base calls in nanopore data
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University of Saskatchewan, Canada
Oxford Nanopore Technologies MinION DNA sequencer provides users with large amounts of genomic data in real-time. In addition to the sequence itself, detailed event information is available that includes signal trace, time, and model state of each nanopore. While there are sequencing errors associated with nanopore sequencing, there are not interactive ways for users to assess specific base-pair positions in terms of whether sequence variation corresponds to technical error or true biological diversity. We have developed a REST-API that provides efficient retrieval of data from nanopore FAST5 data. This API has been connected with a front-end visualization extending Pileup.js and making use of Data Driven Documents (D3.js). Together the API and front-end enable a visualization platform for interactive analysis of nanopore signal data to confirm sequence base calls and this software is suitable for use in a mobile setting.
Matthew Links is an Assistant Professor in the Department of Animal and Poultry Science and an associate member of the Computer Science Department at the University of Saskatchewan. His interests in the microbiome have involved numerous contexts: enhanced oil recovery, the rhizosphere, infectious diseases as well as plant and animal health. In these settings Dr. Links’ work has demonstrated that cpn60 is a robust DNA barcode that can be used in microbial profiling studies and provides significant advantages over other genes commonly used for microbial profiling. Recent work has resulted in a novel enrichment technique for microbial profiling (Capture-Seq) that eliminates the need for universal PCR and dramatically reduces the amount of shotgun sequencing data required to gain quantitative information about microbiota from any ecological niche. Matthew’s current work with nanopore sequencing is focused on allowing researchers to interrogate the signal data directly. A key goal of his work is to enable visualization of signal event data in a way that allows a researcher to assess whether a base call was in error, whether the sample was actually from a mixed sample, or represents a heterozygote.
Recent publications
Albert, A. Y. K. et al. A study of the vaginal microbiome in healthy Canadian women utilizing cpn60-based molecular profiling reveals distinct Gardnerella subgroup community state types. PLoS ONE 10, (2015).
Links, M. G. et al. Simultaneous profiling of seed-associated bacteria and fungi reveals antagonistic interactions between microorganisms within a shared epiphytic microbiome on Triticum and Brassica seeds. New Phytologist 202, 542–553 (2014).
Links, M. G., Chaban, B., Hemmingsen, S. M., Muirhead, K. & Hill, J. E. mPUMA: a computational approach to microbiota analysis by de novo assembly of operational taxonomic units based on protein-coding barcode sequences. Microbiome 1, 23 (2013).
Links, M. G., Dumonceaux, T. J., Hemmingsen, S. M. & Hill, J. E. The Chaperonin-60 universal target is a barcode for bacteria that enables de novo assembly of metagenomic sequence data. PLoS ONE 7, (2012).
Jennifer Gardy
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BC Centre for Disease Control
Dr. Jennifer Gardy is a Senior Scientist at the British Columbia Centre for Disease Control, and holds the Canada Research Chair in Public Health Genomics at the University of British Columbia. Her team pioneered the genomic epidemiology approach to infectious disease outbreak investigation. Her work continues to focus on how genomics can impact communicable disease prevention and control, particularly in the areas of tuberculosis, as well as vaccine-preventable childhood diseases. Jennifer is a member of the National Academies of Science, Engineering, and Medicine’s Forum on Microbial Threats, and a scientific advisor to uBiome and Animalbiome. When not tracking microbes, Jennifer works in science communication - she is a regular science documentary presenter on Canadian national television, and wrote a children’s book about microbes called “It’s Catching: the Infectious World of Germs and Microbes”.
Recent publications
Crisan, A., McKee, G., Munzner, T. & Gardy, J. L. Evidence-based design and evaluation of a whole genome sequencing clinical report for the reference microbiology laboratory. PeerJ 2018, (2018)
Gardy, J. L. & Loman, N. J. Towards a genomics-informed, real-time, global pathogen surveillance system. Nature reviews. Genetics 19, 9–20 (2018)
Guthrie, J. L. et al. Molecular Epidemiology of Tuberculosis in British Columbia, Canada - A 10-Year Retrospective Study. Clinical infectious diseases : an official publication of the Infectious Diseases Society of America (2017). doi:10.1093/cid/cix906
Gardy, J. L. (2017) ‘Mycobacterium chimaera: unraveling a mystery through genomics’, The Lancet Infectious Diseases, pp. 1004–1005. doi: 10.1016/S1473-3099(17)30356-0
Didelot, X. et al. (2017) ‘Genomic infectious disease epidemiology in partially sampled and ongoing outbreaks’, Molecular Biology and Evolution, 34(4), pp. 997–1007. doi: 10.1093/molbev/msw275
Know your onion - the impact of long reads on large genomes
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Wageningen University and Research, Netherlands
Of over the > 300K plant species, approximately 500 are domesticated for use by humankind, although 90% acreage is just occupied by 20 species. However, this indicates that there is quite a diversity of genomes, for which reference genome sequences have been developed. Reference genomes have a wide range of sizes and complexity in terms of repeats and ploidy. From the work on the human genome, it has been shown that long-read technologies, such as the one offered by Oxford Nanopore Technologies, can span and resolve complex sequences which previously could not be assembled. In this presentation, I plan to show the power of long nanopore reads to resolve complex puzzles in plant species and the potential to develop completed platinum standard reference genomes in any of the 500 domesticated plant species. For example, improving the assembly of the 16 Gb highly repetitive genome of the onion (Allium cepa).
Richard Finkers graduated in plant breeding working on the identification of loci contributing to resistance to Botrytis cinerea in the tomato. He now leads a research group which focuses on genomics approaches and big data strategies to improve breeding research. The genomics approach mainly seeks to understand the structure and genetic diversity in large and complex crops, for example the development of methodologies to phase sequence reads in the onion (16Gb diploid outbreeding crop) and the four expected phases in the potato (autotetraploid outbreeding crop). Research in big data focuses on strategies to make heterogeneous types of research data FAIR (findable, accessible, interoperable and re-usable) and as input for novel strategies to develop the crops needed for the future.
Where genomics approaches are bridged with phenomics
Recent publications
Wilkinson, M. D. et al. The FAIR Guiding Principles for scientific data management and stewardship. Scientific Data 3, 160018 (2016)
Aflitos, S. et al. Exploring genetic variation in the tomato (Solanum section Lycopersicon) clade by whole-genome sequencing. Plant Journal 80, 136–148 (2014)
Motazedi, E., Finkers, R., Maliepaard, C. & de Ridder, D. Exploiting next-generation sequencing to solve the haplotyping puzzle in polyploids: a simulation study. Briefings in Bioinformatics bbw126 (2017). doi:10.1093/bib/bbw126
LOGAN: Lossless graph-based analysis of NGS datasets
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RWTH Aachen University
Recent developments in sequencing technologies necessitate matching improvements in bioinformatics tools to effectively utilize it. Existing tools suffer from limitations in both scalability and applicability, which are inherent to their underlying algorithms and data structures. We therefore developed a new data structure, the LOGAN graph, which is based on a memory efficient Sparse De Bruijn Graph, with routing information. Unlike the established Overlap-Layout-Consensus or De Bruijn Graph approaches, this LOGAN approach is suitable for both short-read and long-read sequencing data. Here we present the latest results of applying this approach to short-read, long-read and hybrid datasets.
Anthony Bolger completed a BSc in Computing Applications at Dublin City University in 1997, before starting his working career as a consultant. He later set up a software consulting company with a fellow graduate, and after a successful 6 years, relocated to Madrid to pursue an industry position where he served as a Product Architect. Interested in the challenges posed by the rapidly-developing bioinformatics field, Anthony began working in the Max Planck Institute for Plant Physiology in Potsdam in 2009, first as a computational biologist and then as a PhD researcher. He then moved to RWTH Aachen in Germany where he currently works as a post-doc and bioinformatics team lead.
Making infection control in hospitals smarter using nanopore sequencing
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Genome Institute of Singapore
The emergence of multi-drug resistant bacteria has made effective and targeted infection control in hospitals even more important to save the lives of at-risk patients. Hospital environments are known to be enriched for antibiotic resistant organisms, but their distribution and transmission across different sites and rooms remains largely untracked. As part of the MetaSUB consortium, we are using nanopore sequencing to study the resistomes associated with various hospital environments and develop baseline maps for hotspots and transmission patterns. By constructing near-complete genomes from metagenomic samples, we are able to identify novel plasmids containing resistance genes, as well as track their spread through hospital environments. This work is building toward the development of “Smart Hospitals” in Singapore where real-time surveillance of pathogens in the environment enables targeted and effective infection control measures.
Dr. Nagarajan is Associate Director and Senior Group Leader in the Genome Institute of Singapore, and Adjunct Associate Professor in the Department of Computer Science at the National University of Singapore. His research focuses on developing cutting edge genome analytical tools and using them to study the role of microbial communities in human health. His team conducts research at the interface of genetics, computer science and microbiology, in particular using a systems biology approach to understand host-microbiome-pathogen interactions in various disease conditions. Dr. Nagarajan received a B.A. in Computer Science and Mathematics from Ohio Wesleyan University in 2000, and a Ph.D. in Computer Science from Cornell University in 2006, advised by Prof. Uri Keich. He did his postdoctoral work in the Center for Bioinformatics and Computational Biology at the University of Maryland working on problems in genome assembly and metagenomics with Prof. Mihai Pop.
Mapping multi-contact chromatin interactions on the MinION
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University Medical Center Utrecht, Netherlands
Chromatin folding is increasingly recognized as a regulator of genomic processes such as gene activity. Chromosome conformation capture (3C) methods have been developed to unravel genome topology through the analysis of pair-wise chromatin contacts and have identified many genes and regulatory sequences that, in populations of cells, are engaged in multiple DNA interactions. However, pair-wise methods cannot discern whether contacts occur simultaneously or in competition on the individual chromosome. We present a novel 3C method, Multi-Contact 4C (MC-4C), that applies nanopore sequencing to study multi-way DNA conformations of tens of thousands of individual alleles for distinction between cooperative, random and competing interactions. MC-4C can uncover previously missed structures in sub-populations of cells. It reveals unanticipated cooperative clustering between regulatory chromatin loops, anchored by enhancers and gene promoters, and CTCF and cohesin-bound architectural loops.
Dr. de Ridder is Principle Investigator / Associate professor in Bioinformatics. His lab specializes in creating novel computational strategies and algorithms that transform, normalize, integrate and mine large volumes of data. Much of his research floats on machine learning approaches. His recent work has focussed on computational approaches to map chromatin interactions using long-read sequencing platforms.
Recent publications
Allahyar, A. et al. Locus-Specific Enhancer Hubs And Architectural Loop Collisions Uncovered From Single Allele DNA Topologies. bioRxiv 206094 (2017). doi:10.1101/206094
Matt Loose
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University of Nottingham
Dr Matt Loose is based at the School of Life Sciences, University of Nottingham. A developmental biologist and bioinformatician, he also heads up DeepSeq, the University of Nottingham next-generation sequencing service. The DeepSeq lab is equipped with MinION, GridION and now PromethION. DeepSeq actively encouraged Nottingham Academics to apply to join the Nanopore Community and, in return, supported participants with both library prep and bioinformatics, and led to the development of tools including MinoTour and also working on Read Until. Matt was initially interested in the generation of long-reads to sequence novel genomes alongside real-time analysis of MinION data. To that end, he recently co-led with Prof Nick Loman the sequencing and assembly of the first reference human genome on the MinION. DeepSeq also have a small urn in their possession, although perhaps not for much longer.
Recent publications
Jain, M. Nanopore sequencing and assembly of a human genome with ultra-long reads. Nat Biotechnol 36(4) 338-345 (2018) doi: 10.1038/nbt.4060
Loose, M. W. The potential impact of nanopore sequencing on human genetics. Human Molecular Genetics 26, R202–R207 (2017)
Quick, J. et al. Multiplex PCR method for MinION and Illumina sequencing of Zika and other virus genomes directly from clinical samples. Nature Protocols 12, 1261–1266 (2017).
Faria, N. R. et al. Establishment and cryptic transmission of Zika virus in Brazil and the Americas. Nature 546, 406–410 (2017)
Votintseva, A. A. et al. Same-day diagnostic and surveillance data for tuberculosis via whole-genome sequencing of direct respiratory samples. Journal of Clinical Microbiology 55, 1285–1298 (2017)
Jain, M. et al. MinION Analysis and Reference Consortium: Phase 2 data release and analysis of R9.0 chemistry. F1000Research 6, 760 (2017)
Loose, M., Malla, S. & Stout, M. Real-time selective sequencing using nanopore technology. Nature Methods 13, 751–754 (2016)
Ip, C. L. C. et al. MinION Analysis and Reference Consortium: Phase 1 data release and analysis. F1000Research (2015) doi:10.12688/f1000research.7201.1
Measuring the transcriptome of the C. elegans lifecycle using direct RNA sequencing
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Johns Hopkins University, USA
Though regulation of gene expression is central to organism development and disease, there are many open questions about the dynamic nature of gene regulation through development. Here, we take advantage of direct RNA nanopore sequencing (dRNA-seq), to explore some aspects of transcriptome regulation, including splicing variation, and alternative polyadenylation. We have generated transcriptomes for C. elegans, a classic biological model for the study of development, across developmental stages (L1-L4, YA, GA) of the N2 strain.
C. elegans is a relatively simple metazoan with a fully sequenced genome, a well characterized and invariant cell lineage, and an excellent molecular genetic toolbox. It is an ideal system for exploratory development of new genomic technologies, such as the full-length transcript sequencing we propose here. By sequencing full-length transcripts across development, we provide a first look at identification of the diversity and transcript architecture of the transcriptome.
We assessed the prevalence of different splicing and 3’UTR isoforms across our samples, initially focusing on a few genes. In addition, we used a hidden markov model, implemented as part of the nanopolish suite, to estimate poly-A tail lengths, and compare lengths across samples and isoforms.
Nathan Roach is a PhD candidate in the labs of James Taylor and John Kim at Johns Hopkins University in the Cellular Molecular and Developmental Biology department.
Metagenomic nanopore sequencing: RNA viruses from lab to field
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Public Health England
Emerging and re-emerging RNA viruses cause a significant global disease burden, ranging from mild febrile illness to haemorrhagic fevers. Rapid and unbiased identification methods, such as metagenomic MinION sequencing, are vital for the identification and characterisation of emerging pathogens for which little prior knowledge is available. Portable methodologies for field use are required during such outbreaks, especially when they occur in resource-limited settings. We have investigated a range of clinical samples using a Sequence Independent Single Primer Amplification approach and have demonstrated that metagenomic MinION sequencing can elucidate full viral genomes directly from clinical samples for Chikungunya, Dengue and Lassa virus; across clinically relevant range of viral titers. Following our results we mobilized a research team and deployed in Nigeria to test and investigate the establishment of field metagenomic sequencing using the MinION. Our pilot study was expedited and utilized to support the largest reported outbreak of Lassa fever (LASV) in Nigeria.
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Liana is a PhD student based at Public Health England; her project is part of the NIHR Health Protection Research Unit in Emerging and Zoonotic infections, a collaboration between Public Health England and the University of Liverpool. Her work focuses on investigating the application of metagenomic sequencing methods to viral clinical samples. Liana is interested in field sequencing, and utilised the MinION for metagenomic sequencing in Nigeria during the recent Lassa fever outbreak.
MinION in the marine environment: from identifying tetrodotoxin producers to tracing sharks and rays using eDNA
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Wageningen University & Research
We study marine ecology using molecular biology. In recent years, every summer the neurotoxic Tetrodotoxin (TTX) is found in Dutch mussels and oysters, exceeding levels allowed for human consumption. TTX is produced by bacteria, and accumulates in the animal host. The gene cluster encoding TTX biosynthesis is unknown, and the microbial source of the Dutch TTX outbreak is not identified. We therefore isolated metagenomic DNA from TTX positive shellfish and used nanopore sequencing to identify TTX producing microorganisms and their TTX biosynthetic gene clusters. In another project we survey marine biodiversity. Offshore wind farms in the North Sea are assumed to attract large marine animals, since they provide a diverse habitat with increased biodiversity and shelter. Using a mobile sequencing laboratory, we aim to amplify and sequence environmental DNA (eDNA) directly on-site, to investigate the presence of large marine animals such as sharks and rays. Both applications demonstrate the opportunities of mobile, real-time, long-read sequencing enabled by the MinION.
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Reindert Nijland is an Assistant Professor at the Marine Animal Ecology group at Wageningen University, Netherlands. Since obtaining his PhD in molecular microbiology at University of Groningen, Netherlands, he has studied the interaction of bacteria with a diversity of hosts. At the Dove Marine Laboratory, Newcastle University, UK, he worked on biofilms of marine Bacillus species isolated from seaweed. After returning to the Netherlands, he studied bacterial pathogens and their interactions with the human and bovine immune systems at UMC Utrecht. In 2014, he again switched host organism, and joined Wageningen University to study the interactions of bacterial pathogens with their plant hosts. Reindert has a strong passion for marine biology, especially crabs. He enjoys scuba diving, underwater photography and underwater filming. In 2017, he could no longer resist the attraction of the marine environment, and joined the Marine Animal Ecology group. His current focus is on the interaction between marine hosts and their microbes. He developed approaches to identify microbial toxin gene clusters in shellfish. He also works on the development of methods for rapid on-site identification of eukaryotes such as crabs, fish and marine mammals by analysing environmental DNA (eDNA) using nanopore sequencing with the MinION.
Multi-contact chromosome conformation capture using nanopore sequencing in nematodes
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University of Bern
A wealth of studies has shown that gene regulation occurs at different scales, ranging from the promoter to the localization of the gene inside the nuclear space. Our laboratory studies dosage compensation in the nematode C. elegans, in which a condensin-like complex modifies the three-dimensional folding and position of the X chromosome, and down-regulates expression of X-linked genes. To understand how chromosome folding impacts gene expression, we use chromosome conformation capture (3C) technologies. For 3C, chromatin is cross-linked before DNA is digested in situ by a restriction enzyme. The restriction fragments are then ligated together, leading to formation of “contact” molecules in which fragments distant on the linear genome are ligated together. The 3D proximity of fragments makes them more likely to get ligated. One of the main limitations of 3C is the fact that each end of restriction fragments can be ligated only once, meaning that one can only identify pair-wise interactions and multi-way interactions can only be inferred from contact frequencies averaged over many cells. To overcome this limitation and to characterize gene conformation in single cells, we use nanopore long-read sequencing, thereby capturing many contacts per sequenced molecule. Initial results using this technology will be presented.
Peter Meister completed his PhD in Molecular and Cellular Genetics at Institut Curie/University of Paris before completing a post-doc at the Friedrich Miescher Institute in Basel. Since 2011 he has been group leader of the Cell Fate and Nuclear Organization Laboratory at University of Bern.
Nanopore sequencing in clinical diagnostics
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ViaPath at Guy's, St Thomas's & King's College Hospitals
Team Nanopore at Viapath Clinical Laboratories at Guy's, St Thomas's and King's College Hospitals are exploring ways in which the rapid production of long-reads on commodity hardware can be exploited to transform Healthcare Genomics. Whilst base call accuracy of single molecule long-reads is not yet as high as for short-read clusters, unambiguous mapping of long reads opens up unique possibilities not accessible to short-read technology. Furthermore HMM tools can readily be applied to improve the signal:noise ratio to diagnostic standards. We will illustrate how one-step tests can identify gene deletions with base-pair accuracy, trinucleotide repeat expansions in single-reads and report haplotypes directly over kilobase ranges.
Graham Taylor was Head of the Regional Genetics Laboratory in Leeds with a long-standing interest in translating genomic technology into diagnostics. In 2006 he led a UK Department of Health Funded project “New genetic diagnostic technologies for consanguineous families at risk of recessive genetic disease” and moved to Cancer Research UK as Director of Genomic Services, where he led an evaluation of next-generation sequencing technology.
In 2009, as Head of the Genomics Translation Unit in Leeds, his team developed methods for diagnostic amplicon sequencing in fixed tissue, copy number variation analysis and streamlined conventional genetic testing using next-generation sequencing. In 2012 he joined the Department of Pathology at Melbourne University as the Herman Professor of Genomic Medicine, Director of the Australian Node of the Human Variome Project and Director of the Victorian Clinical Genetics Laboratories, helping to accredit both laboratories for exome-based clinical diagnostics.
From February 2016 he took up the post of Scientific Director of Clinical Genomics with ViaPath at Guy’s & St. Thomas’s Teaching Hospitals in London. Current research interests are around applications of long sequencing read technology in genetic diagnosis.
Nanopore sequencing in veterinary virology: from clinical sample to whole genome
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University of Toulouse
avipoxviruses (APV), resulting in cutaneous and/or tracheal lesions, and belong to the Poxviridae family as well as the variola virus. Poxviruses share large genome sizes (from 130 to 360 kb), featuring repetitions, deletions or insertions as a result of a long-term recombination history. This disease may have a major economic impact in gallinaceous poultry and is an emerging concern for wildlife. Two independent cases of fowlpox were diagnosed in commercial layer farms in western France. All tracheal swabs and tissues sampled in both farms tested PCR positive for fowlpoxvirus. Using Oxford Nanopore Technologies sequencing, we readily generated whole APV genomes from cutaneous or tracheal lesions, without any isolation or PCR-based enrichment. Fowlpox virus read loads ranged from 0.75% to 2.62 %. The long read size eases the assembly step and lowers the bioinformatics capacity requirements and processing time compared to huge sets of short reads.
Guillaume completed a PhD in 2017 on the detection and characterization of respiratory pathogens using high-throughput PCR and next-generation sequencing methods. In November 2017 he joined the Chair of Biosecurity at the Veterinary School in Toulouse as an engineer in charge of the Clinical Diagnostics lab and development of new molecular tools for the detection and characterization of viral genomes.
Nanopore sequencing of cancer genomes
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University Medical Centre Utrecht, Netherlands
Cancer genome sequencing is taking central stage in oncology. Despite improvements in genomics technology, the detection of structural variants from short-read cancer genome sequencing still poses challenges, particularly for complex variation. I will highlight our work on the generation of long-read sequencing data for cancer genomes and the extraction of high-quality sets of somatic structural variations from these data. I will further discuss experiments on the use of somatic breakpoints and mutations to track cancer in liquid biopsies using nanopore sequencing
Dr. Wigard Kloosterman is Group Leader and Associate Professor at the Department of Genetics within the Center for Molecular Medicine at the University Medical Center Utrecht in The Netherlands. The Kloosterman group has strong expertise in cancer genomics, bioinformatics and nanopore sequencing technology. Dr Kloosterman received a PhD from Utrecht University.
Nanopore sequencing of full-length 16S rRNA gene in low-biomass samples: subclinical mastitis in water buffalo
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Nanopore sequencing permits de novo assembly of repetitive microbial genomes
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Nanopore sequencing-based diagnostics of bacteremia in septic patients
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NanoSV
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University Medical Centre Utrecht, Netherlands
NanoSV is a software package that can be used to identify structural genomic variations in long-read sequencing data, such as data produced by Oxford Nanopore Technologies’ MinION, GridION or PromethION instruments. The core algorithm of NanoSV identifies split mapped reads and clusters the split-mapped orientations and genomic positions to identify breakpoint-junctions of structural variations.
Jose Espejo Valle-Inclan is a PhD student in the group of Wigard Kloosterman at the University Medical Center in Utrecht, Netherlands. His research centres on cancer genomics, particularly on ovarian cancer and focusing on the role and detection of structural variation. He holds a BSc in Biochemistry from the Autonomous University of Madrid, Spain and an MSc in Bioinformatics from the Wageningen University, Netherlands.
Native RNA sequencing of human polyadenylated transcripts
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University of California, Santa Cruz
On behalf of the Nanopore RNA Consortium (Akeson, Brooks, Loman, Loose, Paten, Simpson, Timp, and Snutch laboratories), I will present a preliminary analysis of 13 million human polyadenylated native RNA sequence reads for the GM12878 model cell-line. This analysis includes descriptions of full-length transcripts up to 22kb, alternative isoforms, polyA tail length, and RNA modifications. Additionally, ~24 million cDNA nanopore reads were obtained from the same RNA samples, which permit direct comparison of both transcriptome profiling methods.
Angela Brooks is an Assistant Professor of Biomolecular Engineering at UC Santa Cruz. Her research group focuses on identifying cancer genome alterations that disrupt gene regulation, particularly through RNA splicing. Angela has expertise in transcriptome sequencing analysis, cancer genomics, functional genomics, and bioinformatics. She received her Ph.D. from UC Berkeley and was a post-doctoral fellow at the Dana-Farber Cancer Institute and the Broad Institute.
On-site nanopore sequencing of Darwin's finch genomes in the Galapagos
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Uppsala University, Sweden
The Galapagos Islands are situated in geologically young archipelago about 900 km west of continental Ecuador. Owing to their recent origin, their isolated location and strong conservation efforts, the islands boast a rich repertoire of endemic species of both plants and animals. Perhaps most famous among endemic species are the Darwin's finch, 18 species of passerine birds that evolved from a common ancestor in the last 1.5-2.0 million years in a remarkable adaptive radiation affecting body size and beak morphology. During his travels around the world, Charles Darwin visited the Galapagos and collected these finches that so beautifully illustrate his theory of evolution of phenotypic diversity due to natural selection. For a two week expedition in March/April 2018, we went to San Cristóbal island in the Galapagos to sequence birds representing all the major phylogenetic groups of Darwin’s finches. From each bird we collected a small amount of blood then isolated DNA, made sequencing libraries and sequenced birds representing seven species of Darwin's finches using GridION/MinION and 48 flow cells, for a combined yield of around 200 Gb. In this presentation I will present our de novo Darwin's finch genome assembly, inter-species contrasts for structural variants (SV), as well as our inference regarding the importance of such SV’s on the adaptive radiation.
Carl-Johan Rubin received his PhD in Molecular Medicine at Uppsala University in 2008. As a postdoc in the Leif Andersson lab in Uppsala, he used short-read sequencing methods to explore the genetics of chicken, porcine and rabbit domestication. Current research interests include quantitative genetics and genomics studies in Equidae, Atlantic salmon and Atlantic halibut, as well as evolutionary genetics of natural populations such as Darwin’s finches, rabbits and Atlantic herring.
Recent publications
Lamichhaney, S. et al. Evolution of Darwin’s finches and their beaks revealed by genome sequencing. Nature 518, 371–375 (2015).
Phasing regulatory SNVs to their regulating transcript regions in cancers by using MinION
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Pilon
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Broad Institute, USA
Pilon is a software program which takes a genome assembly along with sequencing reads aligned to it as input and analyzes the read data for evidence of differences between the sequencing and assembly. When used with sequencing data from the same organism aligned to a draft genome, Pilon will output an improved assembly after identifying and fixing several kinds of discrepancies. When used with sequencing data from a closely related organism aligned to a reference genome, Pilon will call variants, which can be output as a VCF file. Pilon has been available for several years, and has become a widely used tool for "polishing" draft assemblies created from less accurate long-read technologies by overlaying high quality short-read data to improve local base quality. I have recently started new development work to enhance Pilon to use long read data from Oxford Nanopore and PacBio sequencing directly, and I will demonstrate both the old and new capabilities.
Bruce Walker is Vice President of Technology at Applied Invention, as well as Visiting Scientist at the Broad Institute of MIT & Harvard, where he previously worked for over 10 years as Director of IT and Director of Genome Assembly and Analysis. Bruce holds a B.Sc. in Physics from MIT, and has spent most of his career developing scalable, high-performance computing architectures and algorithms.
Point of care Mycobacterium tuberculosis whole genome sequencing in remote rural Madagascar
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Stony Brook University - Global Health Institute & Pasteur Institute of Madagascar
Tuberculosis (TB) remains the leading infectious disease killer globally, with 10.4 million new cases in 2016 among which 4.1 million remain undiagnosed. Current approaches to TB control are predicted to fail to meet the World Health Organization objective to eliminate TB by 2030. With the rise of the multi-drug resistant tuberculosis (MDR-TB) epidemic, new innovative TB case finding, diagnosis, and control strategies are needed. Our objective is to achieve real-time TB diagnosis at the point of care, comprehensive genotypic drug susceptibility testing, and molecular epidemiology driven interventions in low resource, high burden settings. In April 2018, the Pasteur Institute of Madagascar, University of Oxford’s Modernizing Medical Microbiology group and Stony Brook University’s Global Health Institute launched a prospective pilot project which includes methods development for TB sequencing from sputum, and integration of portable TB DNA sequencing within National TB Program (NTP) clinical infrastructures and in collaboration with clinicians and policymakers.
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Simon Grandjean Lapierre is a trained infectious diseases specialist and medical microbiology physician with previous clinical, laboratory and infection control experience in sub-Saharan African countries. He holds post-doctoral graduate degrees in global health and molecular diagnostics applied mycobacterial diseases. He currently works as a clinical lecturer in Centre Hospitalier de l'Université de Montréal in Canada, and coordinates the tuberculosis research program of Stony Brook University in Madagascar. His research activities focus on the implementation of new point of care and highly fieldable technologies for tuberculosis control.
Niaina Rakotosamimanana is a microbiologist and lab director of the Mycobacterial Unit of the Pasteur Institute of Madagascar in charge of the tuberculosis research program. This includes operational research that evaluates new TB diagnostic tools and drug resistance surveys in collaboration with the National Tuberculosis Control Program (NTCP) of the Malagasy Ministry of Public Health. He is in the steering committee of the international network for data analysis that aims to coordinate NGS data handling and NGS capacity building inside the Pasteur Institute international network that is present in 33 countries worldwide.
PromethION sequencing of complex plant genomes
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Keygene, Netherlands
KeyGene operates at the forefront with respect to new technologies and innovations in the field of plant genomics, and participates in the PromethION Early Access Program (PEAP). Genome sequencing initiatives of large, complex genomes typically yield highly fragmented genome assemblies. Using the PromethION, that offers ultra-long reads and high sequence output, KeyGene aims to produce contiguous, high-quality genome assemblies of plant pathogens and complex plant genomes. Recently we finished the data generation of the 2.7 Gbp lettuce genome and generated >100X coverage with just a few flow cells. To obtain high quality libraries for sequencing, the HMW DNA quality (integrity and purity) is crucial. KeyGene has developed specific knowledge in this area, and its impact on read length and yield will be presented and discussed.
Alexander Wittenberg graduated with an MSc in plant breeding and crop protection at the Wageningen University and completed his PhD at the Laboratory of Plant Breeding. Here he focused on the development of innovative genotyping methods to study the origin of genome plasticity in crop plants and their wild relatives. In 2007 he joined KeyGene, where he continued his work on the development and application of molecular marker methods. Alexander acquired considerable experience in the field of next-generation sequencing, with expertise on a wide range of platforms and applications. Currently he is a scientist contributing to the development of sequence-based technologies in KeyGene’s accelerated molecular breeding platform. Alexander was involved in the early evaluation of the technology during the MAP, and is now actively involved in the PromethION early access program, GridION and VolTRAX (VIP), as well as bringing this technology to the market for KeyGene’s clients.
Recent publications
Datema, E. et al. The megabase-sized fungal genome of Rhizoctonia solani assembled from nanopore reads only. bioRxiv 084772 (2016). doi:10.1101/084772
PromethION: an alpha machine in production
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LMU Munich
Andreas Hauser is a Staff Scientist, for the Laboratory for Functional Genome Analysis, at Gene Center Munich, LMU. He is also an entrepreneur.
Recent publications
Remmert, M., Biegert, A., Hauser, A. & Söding, J. HHblits: Lightning-fast iterative protein sequence searching by HMM-HMM alignment. Nature Methods 9, 173–175 (2012).
Greif, P. A. et al. Somatic mutations in acute promyelocytic leukemia (APL) identified by exome sequencing. Leukemia 25, 1519–1522 (2011) doi: 10.1038/leu.2011.114.
PromethION: Unleash the power of nanopore sequencing
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LMU Munich
The recently available nanopore sequencing technology provides fantastic new possibilities in the field of DNA and RNA sequencing. It promises access to long sequence reads of DNA and RNA without significant investments in sequencing hardware and furthermore, direct detection of DNA and RNA modifications. More recently the PromethION was announced as the most powerful nanopore sequencer with an output in the range of 100GB per flow cell. Here, we provide insights in our experiences with the alpha version of the PromethION. Based on selected samples we will show the results obtained with the PromethION in the field of genetics, leukaemia and stem cell differentiation, and the challanges that we faced.
Helmut Blum heads the Genomics group in the Laboratory for Functional Genome Analyses at the Gene Center of the Ludwig-Maximilians-University of Munich. This group operates a technology platform for short and long-read sequencing and bioinformatic analysis. The platform provides a variety of library preparation methods and comprehensive sequencing for their own scientific projects and various collaborations in the field of life sciences. Currently the group extends its field of action towards high-output long-read sequencing with the PromethION sequencer.
Rapid bacterial identification from clinical samples using nanopore sequencing
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Seoul National University Hospital
Rapid detection of the pathogen is the most important step in the management of patients with infectious diseases. In this talk, I will share my research experiences of rapid bacterial identification from clinical samples using nanopore sequencing. Sequence-based pathogen identification directly from clinical samples has many advantages over the traditional culture-based methods. Nanopore sequencing of the 16S rRNA gene enables rapid diagnosis of bacterial infections, including polymicrobial infection and anaerobic infection, which will be very useful in the real clinical setting.
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Jangsup Moon, MD, PhD is a neurologist interested in metagenomic pathogen detection using nanopore sequencing. He received his MD in 2005 and finished his Neurology residency training at Seoul National University Hospital in 2013. He received his PhD in Neuroscience at the College of Medicine, Seoul National University School in 2015. He is currently working as an Assistant Professor in the Department of Neurosurgery and Neurology at Seoul National University Hospital.
Recent publications
Moon, J. et al. Campylobacter fetus meningitis confirmed by a 16S rRNA gene analysis using the MinION nanopore sequencer, South Korea, 2016. Emerging Microbes and Infections 6,(2017)
Real-time selective sequencing with RUBRIC
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Sandia National Laboratories
Building upon the pioneering Read Until work of Matt Loose and his team, we have demonstrated an integrated real-time selective sequencing software architecture dubbed RUBRIC (Read Until with Basecall- and Reference-Informed Criteria). Unlike the event trace (“squiggle”) pattern matching approach previously described for Read Until, RUBRIC combines real-time basecalling and rapid, on-the-fly alignment to conventional ACTG reference sequences as the basis for molecule-by-molecule DNA selection and target enrichment. In addition to providing operational flexibility and scalability in choosing references for target selection, the RUBRIC system can be effectively implemented using off-the-shelf PCs rather than cluster computing platforms. We evaluate the performance of the RUBRIC method in detail, with particular attention to lessons learned in implementing this approach. We also assess the implications of fully optimized RUBRIC-based target enrichment for applications like point-of-care pathogen diagnostics and metagenomic analysis.
Dr. Michael Bartsch is a Principal Member of the Technical Staff in the Exploratory Engineering Solutions department at Sandia National Laboratories in Livermore, California. Before joining Sandia in 2005, Michael received a B.M.E from the University of Dayton, and M.S. and Ph.D. degrees in mechanical engineering from Stanford University. Dr. Bartsch has extensive, applied R&D experience leveraging microscale phenomena, high-resolution sensing, microfluidics, thermal analysis, microsystems engineering, and finite element modeling to address a variety of multidisciplinary applications and enable novel modes of scientific exploration. His most recent work has focused on applying highly integrated and automated microfluidic system architectures and innovative fluid manipulation technologies to problems in next-generation sequencing, DNA forensics, analytical chemistry, and materials science. Michael is currently the principal investigator of the Real-time Automated Pathogen Identification by Enhanced Ribotyping (RAPIER) project, an effort seeking to leverage the capabilities of the Oxford MinION nanopore sequencer for pathogen diagnostics.
Recent publications
Krishnakumar, R. et al. Systematic and stochastic influences on the performance of the MinION nanopore sequencer across a range of nucleotide bias. Scientific Reports 8, (2018)
Bartsch, M. S. et al. The rotary zone thermal cycler: A low-power system enabling automated rapid PCR. PLoS ONE 10, (2015)
Kim, H. et al. A microfluidic DNA library preparation platform for next-generation sequencing. PLoS ONE 8, (2013)
Jebrail, M. J., Bartsch, M. S. & Patel, K. D. Digital microfluidics: a versatile tool for applications in chemistry, biology and medicine. Lab Chip 12, 2452–2463 (2012)
Thaitrong, N. et al. Quality control of next-generation sequencing library through an integrative digital microfluidic platform. Electrophoresis 33, 3506–3513 (2012)
Kim, H. et al. Automated digital microfluidic sample preparation for next-generation DNA sequencing. Journal of Laboratory Automation 16, 405–414 (2011)
Redefining the Arabidopsis thaliana transcriptome with DRS sequencing
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Resistome accumulation induced by discharge of treated domestic wastewater - an overlooked aspect of modern wastewater treatment
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Southern University of Science and Technology (SUSTech), China
Nanopore has become the leading 3rd generation sequencing platform in recent years, and has been widely applied in clinical and environmental researches with promising outcomes. In the present study, nanopore metagenomic sequencing was applied to investigate the microbiomes and antibiotic resistance genes (ARGs) from wastewater treatment plants (WWTPs) and the environment impacted by the WWTPs effluent, which include 1) resistome quantification in influent, activated sludge and effluent of WWTPs, 2) pathogen regrowth in the receiving water after treatment, 3) phenotype-genotype correlation (including both chromosome and plasmid) of multi-drug resistant coliforms in treated effluent and pure culture of E. coli. A convenient and efficient workflow was developed for rapid ARGs detection and host tracking based on nanopore data sets. Overall, this work presents rapid and efficient resistome characterization by nanopore technology that could facilitate ARGs monitoring and control in hotspots, such as WWTPs and the impacted environments.
Yu Xia is Assistant Professor of Southern University of Science and Technology (SUSTech), and received her PhD from the University of Hong Kong. Her research interest focuses on utilizing nanopore sequencing to understand the community ecology and functional synergy among microbes that are crucial for biological wastewater treatment or important for nature material cycles. The topics she currently works on include: environmental dissemination of antibiotic resistance genes (ARGs); direct interspecies electron transfer (DIET) capable microbes in anaerobic sludge digestion; sulfate/nitrate reduction mediated anaerobic methane oxidation (AOM) in coastal sediment. Additionally, she has served as the Young Ambassador of Hong Kong region for American Society for Microbiology (ASM) and the General Secretary for the Postgraduate Student Association (PGSA) of the University of Hong Kong.
Sequencing everything with PromethION
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University of York
The York Genome Centre is based in a department with very wide-ranging research interests. As a result, we receive highly diverse samples to sequence, each with their own quirks. Our nanopore projects range from single microbial species to large plant genomes and metagenomes. We will discuss the requirements associated with sequencing and the analysis of such a broad range of samples, the library preparation methods we use, and discuss the challenges of analysing microbial communities from anaerobic digesters on the MinION and how these scale to the PromethION. Along the way, we will also describe a very efficient method for completely killing flow cells…
Sally is a Technical Specialist in Genomics for the University of York’s Bioscience Technology Facility. She completed her PhD in medical science at the University of Birmingham in 2008, and held post-doctoral positions studying stem cell biology and gene regulation at the University of Leeds, and then the University of York. She plays a key role in providing next-generation sequencing services and solutions to users within the University and further afield, and was an early adopter of nanopore sequencing technologies.
Shaking up the short reads - using MinION sequencing to enhance an outbreak investigation
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University of Cambridge
Antimicrobial resistance (AMR) is a global health concern and causes healthcare-associated infections with limited antibiotic treatment options. Outbreaks of healthcare associated pathogens can spread rapidly and silently particularly in the case of asymptomatic carriage. Methicillin-resistant Staphylococcus aureus (MRSA) has been a public health concern for decades and causes a multitude of infections including skin and soft tissue, bone and joint, pulmonary and blood stream. Hospitals in the United Kingdom have a ‘zero tolerance’ policy towards healthcare-associated MRSA blood stream infections, meaning the yearly ceiling for these cases is zero. Therefore, outbreaks can have major clinical implications for patients and financial penalties for hospitals. Rapid and high-resolution investigation using next-generation sequencing technology can inform outbreak investigations and aid clinicians in bringing them to a close. During February 2018 Infection Control clinicians in our hospital identified an increase in MRSA positive carriage swabs in patients who had been negative during admission screening. All positive cases were located on two adjacent wards. The wards did not mix patient or staff populations but shared an equipment area. We used Oxford Nanopore Technologies MinION sequencing device to obtain rapid long-read MRSA genomic data for nine positive screening swabs. We performed a proof of principle investigation to determine whether robust, informative data could be obtained in a clinically-relevant turnaround time that would determine the extent of the outbreak and the relatedness of the cases involved. Using the MinION we were able to report sequence data defining the outbreak within five working days of initial culture. The data enabled exclusion of two isolates based upon genomic differences and determined that the remaining isolates were likely to be acquired via recent transmission. We used two methods of data analysis which produced comparable results in line with epidemiological data. We were able to report the data faster than the reference laboratory and in a clinically relevant turnaround time. Use of rapid sequencing technologies is beneficial in outbreak situations and could save hospitals time and money. However automated analysis pipelines have not yet been developed which currently limits their accessibility and practicality in clinical settings.
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Hayley Wilson is a post-doctoral research associate for Dr Estée Török in her newly established research group at the University of Cambridge. She completed her PhD in 2016 under the supervision of Professor Sharon Peacock, also at the University of Cambridge. She is currently working on investigating the carriage, transmission and infection of multidrug-resistant bacteria in various patient groups at the Cambridge University Hospitals NHS Foundation Trust. Her work utilises genomic techniques to provide high resolution data in investigating these pathogens and has recently begun working with long-read data produced by the Oxford Nanopore MinION.
Simultaneous methylation and chromatin accessibility profiling on breast cancer models
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Johns Hopkins University
The ability of nanopore sequencing to distinguish modified nucleotides has tremendous potential in exogenous labeling, where one can methylate DNA in a given state, e.g. nucleosome positioning or interactions with specific proteins. Once the DNA is exogenously methylated, we can take advantage of the long-read lengths (>10kb) generated by nanopore sequencing to call methylation across stretches of genomic regions on individual reads. We have previously shown that endogenous CpG methylation can be accurately called using nanopolish, and we have expanded nanopolish modification detection pipeline to detect GpC methylation. We used these models to simultaneously profile nucleosomes and methylation directly on long-reads. Aberrant gene regulation is the source of many diseases including cancer. Two key effectors of this are genomic instability and chromatin states. NOMe-seq has been used previously to characterize chromatin state by probing the endogenous CpG methylation and exogenously labeled nucleosome occupancy. By exogenously labelling nuclei with GpC methyltransferase, cytosines in GpC dinucleotides are methylated in nucleosome-depleted, accessible genomic sites. We have successfully applied this methodology to nanopore sequencing, using nanopolish modification detection pipeline to detect CpG and GpC methylation. We show that using nanoNOMe we can precisely detect nucleosome occupancy along with methylation on individual long-reads. Using the long-reads, we can observe haplotypes, patterns, and correlations of the modifications. Applying nanoNOMe to study the epigenetic state of cancer, we demonstrate our results from performing deeply sequenced nanoNOMe on breast cancer cell lines exhibiting various degrees of malignancy, including MCF10A, MCF-7 and MDA-MB-231.
Isac Lee is a PhD student in the department of Biomedical Engineering at Johns Hopkins School of Medicine. He is being trained in the lab of Dr. Winston Timp, studying the epigenome and genome of cancer. He is interested in epigenomic reprogramming and its association with gene expression and genomic aberrations during cancer progression. He is working on integrating and developing genomic and epigenomic methodologies, and applying them on cancer models and clinical samples.
Single cell transcriptome sequencing with the 10x Genomics Chromium and the MinION
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Soup and nuts: nanopore applications
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Oxford Nanopore Technologies
Dan Turner is Vice President of Applications at Oxford Nanopore Technologies and is a highly experienced scientist who has worked in the field of next-generation sequencing for the last 11 years. Dan provides scientific leadership for multi-disciplinary teams in Oxford, New York and San Francisco. The Applications group aims to bring together sample prep technologies, genomics applications and bioinformatics, to expand the utility of Oxford Nanopore Technologies devices and illustrate the benefits of these technologies to the wider world.
Before joining Oxford Nanopore Technologies, Dan was Head of Sequencing Technology Development at the Wellcome Trust Sanger Institute, and prior to this he held postdoctoral positions at the Sanger Institute and Cornell University Medical College in Manhattan.
The beauty and the beast
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FutureGenomics Technologies
The Netherlands and tulips have for a long time been tightly linked and tulip agriculture is flourishing in our country. But tulip breeding isn’t without problems. Tulip breeding takes a long time and going from tulip seeds to a commercial product takes around 25 years. Pesticide use in tulip agriculture is relatively high so identifying traits that confer resistance to pests is an important issue. Having a tulip genome sequence will assist breeders in a more targeted breeding strategy. The genome of most tulip species is between 20 -35 Gbp which has prevented the sequence and assembly of this genome up until now. Sequencing and assembly of large genomes in general is a real challenge, but with the arrival of the alpha/beta PromethION, producing the sequence data for such a project has become easier. The next challenge is to order all this sequence data in a genome sequence. The long-read scaffolder/assembler Tulip was developed to do this in a reasonable amount of time. I will be discussing the sequencing and assembly of Tulipa gesneriana ‘Orange Sherpa’ using Tulipa-julia, the successor of Tulip.
Hans Jansen is CTO at Future Genomics Technologies based in Leiden in the Netherlands. A molecular biologist with broad experience, his focus has been on the use of next generation sequencing and bioinformatics for genome assembly and transcriptome analysis. As CTO he is responsible for the translation of academic knowledge and novel technologies into usable applications, providing early and easy access to these applications.
Leading the implementation of the MinION at ZF screens, he has been a member of the MARC consortium since it started in 2014. This group was formed to provide independent evaluation of the platform, pool data and analysis techniques, and exchange ideas for how to improve the sequencing protocol or bioinformatic processing.
Having used the MinION, GridION X5, and PromethION in their various genome projects, Hans has a wealth of experience in using the growing number of tools available for nanopore reads, and all from a biologists view point.
The complex architecture of plant T-DNA transgene insertions
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J. Craig Venter Institute
Over the last 35 years the soil bacterium Agrobacterium tumefaciens has been used as the workhorse in the production of transgenic plants through the replacement of its native tumor-inducing plasmid elements with customizable cassettes that enable the random integration of a Transfer DNA (T-DNA) sequence into any plant genome. Due to previous limitations in sequencing read lengths, the architecture of these T-DNA insertions has gone largely uncharacterized. We leveraged Oxford Nanopore Technologies long-reads in combination with optical maps to characterize T-DNA insertions, ranging from 27 to 236 kilobases in the model plant Arabidopsis thaliana. We generated a higher quality reference assembly, which corrected 83% of non-centromeric misassemblies in the platinum hand-curated TAIR10 assembly. For two segregating T-DNA lines we resolved structures up to 36 kb and revealed large-scale translocations events. This unprecedented nucleotide-level definition of T-DNA insertions enabled the characterization of the epigenomic status associated with the insertions.
Dr. Todd Michael is Professor and Director of Informatics at the J. Craig Venter Institute (JCVI) in San Diego, CA USA. At JCVI, Dr. Michael’s group builds genome sequencing, editing and analysis tools with a specific focus on developing synthetic plants. Current projects include sequencing minimal and specialized plant genomes, computationally designing a minimal plant genome, booting-up plant artificial chromosomes, and leveraging nanopore sequencing for complete genomes and epigenomic analysis.
Recent publications
Jupe, F. et al. The complex architecture of plant transgene insertions. bioRxiv 282772 (2018). doi:10.1101/282772
Michael, T. P. et al. High contiguity Arabidopsis thaliana genome assembly with a single nanopore flow cell. Nature Communications 9, (2018).
The detection of 7-deazaguanine in both RNA and DNA using MinION: progress towards studying the function of G-quadruplexes
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De Montfort University
G-quadruplexes (G4s) are RNA/DNA secondary structures, made from G-quartets. G-quartets are formed through a cyclic Hoogsteen hydrogen-bonding arrangement of four guanines with each other, and the planar G-quartets stack on top of one another forming four-stranded helical structures. Several researchers have confirmed their existence in the promoter region of several medically important genes, such as c-MYC and KRAS. Their role has also been shown to affect several post-transcriptional processes, including splicing. Previously we showed that our novel method FoLDeR (Footprinting Of Long Deazaguanine RNA), is able to identify two G4s that regulate the alternative splicing of the apoptotic regulator Bcl-X. However, the presence of 7-deazaguanine substitutions prevents splicing of RNA strands. To resolve this, incorporation of 7-deazaguanine must be restricted to functionally relevant regions. To achieve this aim, a method is required to detect 7-deazaguanine in RNA. By using direct RNA nanopore sequencing we were able to gather sequencing data of both normal and fully substituted 7-deazaguanine RNA. Initial results indicated that 7-deazaguanine causes a massive reduction in sequencing and basecalling rates. Further analysis via Tombo showed that this is due to detectable changes in the ionic current on 7-deaguanines, as well as surrounding nucleotides. This now allows us to programme the Tombo basecaller to relate the changes in currents to 7-deazaguanine. Further work will also be done on the 7-deazadeoxyguanine substitutions in DNA. Ultimately this will provide a new method to study the biological occurrence and function of G4s in splicing and transcriptional control in several disorders such as cancer and cardiovascular diseases.
Dr Carika Weldon is a lecturer in Biomedical Science at De Montfort University in Leicester. Prior to joining the faculty as the youngest lecturer in the university’s history, she obtained her BSc (Hons) Medical Biochemistry in 2011 and her PhD in Biochemistry in 2015 from the University of Leicester.
Dr Weldon’s doctoral work focused on alternative splicing of the apoptotic gene Bcl-X. By creating the new FOLDeR method, she discovered that G-quadruplexes shifts the XS/XL ratio to favour the pro-apoptotic XS isoform. By screening over 30 G-quadruplex ligands, her work identified a suitable drug that could be used for treating cancers, based on its ability to shift the ratio almost 40-fold. In her own lab now she looks at how the presence of G-quadruplexes in pre-mRNA can influence alternative splicing in other genes. She is utilizing the versatile technique of nanopore technology to detect modified guanine with the hopes of gaining more insight into the exciting fields of splicing and G-quadruplexes.
Recent publications
Weldon, C. et al. Specific G-quadruplex ligands modulate the alternative splicing of Bcl-X. Nucleic Acids Research (2017). doi:10.1093/nar/gkx1122
Weldon, C. et al. Identification of G-quadruplexes in long functional RNAs using 7-deazaguanine RNA. Nature Chemical Biology 13, 18–20 (2017).
Tombo: detection of non-standard nucleotides using raw nanopore signal
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Oxford Nanopore Technologies
Tombo is a suite of tools for the identification of modified nucleotides from nanopore sequencing data and visualization of raw nanopore signal. Tombo provides three methods for the investigation of DNA base modifications: specific alternative base detection, canonical (control) sample comparison and de novo canonical model comparison. In addition, Tombo includes a workflow for processing nanopore signal generated by direct RNA sequencing. The advantages and requirements for each detection method will be discussed.
Michael’s graduate and postdoctoral work at Portland State University and Oregon Health Sciences University focused on the biology of gene expression and regulation. Michael then worked as a senior scientific specialist for a leading next-generation sequencing company. He joined Oxford Nanopore Technologies in September 2014 as Technical Applications Manager. He is currently responsible for overseeing US technical support operations.
Tracking movement and evolution of antibiotic resistance plasmids in a hospital over a decade
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Broad Institute
Carbapenem-resistant Enterobacteriaceae (CRE) cause life-threatening infections that are difficult, if not impossible to treat. In order to understand carbapenem resistance and track its spread, we have collected and sequenced hundreds of CRE isolates dating back to 2007. In 2017, carbapenem-resistant Citrobacter freundii were isolated from four different patients at one Boston-area hospital. These isolates had a distinctive arrangement of transposons carrying the carbapenem-resistance gene KPC which was found to be unique to CRE from our study, with 11 out of the 12 isolates containing it having come from the same hospital (2008-2017). Using Unicycler and Pilon on a combination of Illumina and Oxford Nanopore sequencing from these isolates, we obtained finished quality genome assemblies, including fully closed and highly accurate representations of chromosomes and plasmids conferring carbapenem resistance. These assemblies are revealing highly dynamic interactions among two families of plasmids harboring this unique KPC-carrying structure, having moved among three distinct bacterial genera while persisting within a single hospital for a decade.
Bruce Walker is Vice President of Technology at Applied Invention, as well as Visiting Scientist at the Broad Institute of MIT & Harvard, where he previously worked for over 10 years as Director of IT and Director of Genome Assembly and Analysis. Bruce holds a B.Sc. in Physics from MIT, and has spent most of his career developing scalable, high-performance computing architectures and algorithms.
TractION LIMS
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Sanger Institute
TractION is an open source LIMS written by the Production Software team at the Wellcome Sanger Institute. It provides tracking of library preparation and sequencing on the GridION platform.
Beth Flint is a Senior Scientific Manager at the Wellcome Sanger Institute, in Hinxton, South Cambs. She studied Computer Science at UCL and after graduating, started working as a software developer before eventually joining the Wellcome Sanger Institute. Here she has developed Laboratory Information Management Systems (LIMS) for their high throughput library preparation and NGS pipelines. Beth now manages the software development team responsible for developing LIMS in DNA pipelines at the Sanger.
Stephen Inglis works as a developer in production software and has 13 years’ experience of building web applications, previously working in local government and nature conservation. At the Wellcome Sanger Institute he is part of a team that develops and maintains laboratory information systems (LIMS) for the DNA pipelines operation which provides genome analysis services for the Institute. Stephen is also responsible for developing API services to support LIMS, including Labware tracking and barcode printing, as well as working with research and development to build novel software to implement process improvements. His specialist area is developing full stack applications using Ruby on Rails, but is always looking to develop new skills. He is currently building an application to support the library QC process using the front-end JavaScript framework Vue.js.
Understanding transmission dynamics of TB and AMR in the farmland environment
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University of Warwick
Environmental reservoirs of infection within the agricultural landscape are of particular concern because of the risk of indirect transmission between livestock and humans. Long-read sequence technology provides a valuable tool to help better understand dissemination from the environment due to the complexity of environmental matrices, such as soil and faeces. We firstly present a novel method to strain type Mycobacterium bovis, the causative agent of bovine tuberculosis, from both environmental matrices and clinical isolates within the UK. Given the genetic homogeneity of the mycobacterium complex, long-read sequencing was used to genotype M. bovis by quantifying six VNTR regions and the direct repeat region. This has permitted us to develop a rapid and responsive strain typing tool for M. bovis that circumvents the requirement for culture. Furthermore, we present a novel use of the Oxford Nanopore sequencing platform to investigate the drivers and dissemination of antimicrobial resistance in the environment within, and between, livestock producing and residential areas of Karachi, Pakistan. Amplification and sequencing of Class I intergrons, a mobile genetic element often associated with antimicrobial resistance, was used as a proxy for the environmental resistome. Results from this pilot study indicate that the environmental resistome of the two areas were significantly different, with a greater dissimilarity in AMR abundance and diversity seen within chromosomally incorporated integrons.
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Dr Robert James is currently working as a post-doctoral research fellow with Prof. E. Wellington as lead investigator on the BBSRC funded project; “Mycobacterium bovis and the farmland ecosystem: understanding transmission dynamics between animals and the environment.” This collaborative project between the University of Warwick, the Zoological society of London and Imperial College, aims to identify the environmental reservoirs of infection in agricultural land use types, and routes of transmission between mammalian hosts and the environment. Furthermore, Robert has an interest in the evolution and selection of antimicrobial resistance genes in the environment and has recently undertaken work to quantify AMR gene abundances in farmland and residential areas of Karatchi, Pakistan.
Using MinKNOW to assess the quality of your run - The Duty Time Plot
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VirION: Towards long-read viral metagenomics
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University of Exeter, UK
Viruses are the most abundant organisms in the ocean and grease the wheels of global carbon biogeochemistry. Recently, our understanding of viral ecology has taken a major leap forward with the use of viral metagenomics. However, short-read sequencing used for this purpose has its drawbacks — many of the most abundant and important viral taxa fail to assemble and are thus lost from our studies. Here, I will present new methods for using the MinION for long-read viral metagenomics. I will show that these new methods dramatically increase viral diversity captured in marine samples, and provide insight into host-virus interactions in a way that cannot be achieved with short-read technology. I will share our bioinformatic pipelines to improve sequence fidelity, and discuss how MinION technology is bringing us closer to high-throughput single-virus genomics from environmental samples.
Ben Temperton spent 7 years as a professional software engineer before retraining as a marine microbiologist, gaining his PhD from Queens University Belfast. He spent two years as a postdoctoral scholar at Oregon State University with Prof. Steve Giovannoni using metagenomics and metaproteomics to understand the role of the SAR11 clade in global marine carbon biogeochemistry. During this time, he identified four new viruses infecting SAR11 as the most abundant viruses on Earth. Upon his return to the UK, he established the first UK environmental Single Cell Genomics Laboratory at Plymouth Marine Laboratory, before moving to the University of Exeter to set up his own research group studying marine viral ecology and the global impact of predator-prey interactions on carbon remineralisation.