Date: 15th August 2022
Calling methylation in the human genome with PCR-free nanopore sequencing
Methylation plays a fundamental role in regulating gene expression; aberrant methylation patterns are strongly associated with numerous diseases, such as cancer and developmental disorders. The 5-methylcytosine (5mC) modified nucleotide, for example, is an important transcriptional repressor and mediates genomic imprinting.
As PCR amplification is unnecessary for nanopore sequencing, base modifications can be called alongside the canonical nucleotide sequence, with no additional sample preparation. Nanopore sequencing also lacks GC bias, facilitating a consistent read depth, and access to genomic regions that may be inaccessible to traditional methods of sequencing and methylation calling.
Here we present a simple workflow for genome-wide methylation calling from a human blood sample, using the PromethION platform.