Whole-Genome Bisulfite Sequencing with a Small Amount of DNA

Whole-genome bisulfite sequencing (WGBS) is the most widely used method to study DNA methylation profiles across the genome. Since the bisulfite reaction causes DNA degradation, a new approach called post-bisulfite adapter tagging (PBAT) was developed to overcome this problem by adding adapters after bisulfite treatment. In mammals, the PBAT method is used for single-cell bisulfite sequencing (scBS-seq), which enables DNA methylation analysis using a very small amount of DNA from only a few cells, including single-cell input. This protocol involves bisulfite conversion, followed by preamplification and tagging with random hexamer primers prior to Illumina library preparation. Since many procedures are completed in one single test tube, the loss of DNA can be minimized, enabling highly sensitive experiments to study DNA methylation profiles from a very small amount of input material.