Methylation Analysis by Sequencing

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Figure 1. DNA methylation. A methyl group addition to the cytosine carbon 5 in cytosine-phosphate-guanine (CpG) and other nucleotide sequences inhibits the binding of transcription factors to promoters. Click to enlarge.

Many scientists see mapping of the human methylome as a logical follow-up to the Human Genome Project.

Methylation status of DNA varies with age, tissue type, and environmental interactions. A number of diseases such as cancer are marked by altered methylation.

Because the methylome is much more variable than the genome, methylation mapping is inherently more complex than genome sequencing. We offer several strategies to help streamline your research studies.

Next-generation sequencing platforms enable ultra–high-throughput sequencing, mapping, and counting of short DNA reads (tags). In combination with traditional methylation profiling strategies (bisulfite conversion, digestion with methylation-sensitive restriction enzymes, and antibody- or 5-methylcytosine binding protein–based purification), sequencing allows for comprehensive, genome-wide mapping of methylation sites.

And, for targeted analysis of methylation for specific regions, the gold-standard technique is bisulfite sequencing using automated capillary electrophoresis (CE) instruments.