Simultaneous Targeted Methylation Sequencing (sTM-Seq)

Abstract

Mapping patterns of DNA methylation throughout the epigenome are critical to our understanding of several important biological and regulatory functions, such as transcriptional regulation, genomic imprinting, and embryonic development. The development and rapid advancement of next-generation sequencing (NGS) technologies have provided clinicians and researchers with accurate and reliable read-outs of genomic and epigenomic information at the nucleotide level. Such improvements have significantly lowered the cost required for genome-wide sequencing, facilitating the vast acquisition of data that has led to many improvements in patient care. However, the torrid rate of NGS data generation has left targeted validation approaches behind, including the confirmation of epigenetic marks such as DNA methylation. To overcome these shortcomings, we present a rapid and robust protocol for the parallel examination of multiple methylated sequences that we have termed simultaneous targeted methylation sequencing (sTM-Seq). Key features of this technique include the elimination of the need for large amounts of high-molecular weight DNA and the nucleotide specific distinction of both 5-methylcytosine (5mC) and 5-hydroxymethylcytosine (5hmC). Moreover, sTM-Seq is scalable and can be used to investigate multiple loci in dozens of samples within a single sequencing run. By utilizing freely available web-based software and universal primers for multipurpose barcoding, library preparation, and customized sequencing, sTM-Seq is affordable, efficient, and widely applicable. Together, these features enable sTM-Seq to have wide-reaching clinical applications that will greatly improve turnaround rates for same-day procedures and allow clinicians to collect high-resolution data that can be used in a variety of patient settings. © 2019 by John Wiley & Sons, Inc.

Keywords: 5-hydroxymethylcytosine; 5-methylcytosine; DNA methylation.