The mapping of the human epigenome is seen by many scientists as the logical follow-up to the completion of the Human Genome Project.  This epigenomic information will be important in understanding how the function of the genetic sequence is implemented and regulated. Since the epigenome is less stable than the genome, it is thought to be important in gene-environment interactions.

Epigenomic mapping is inherently more complex than genome sequencing, since the epigenome is much more variable than the genome. While each of us has only one genome, our epigenome varies with age, differs between tissues, is altered by environmental factors, and shows aberrations in diseases. So mapping a person’s epigenome at different ages, in different tissue types and disease states, would yield valuable information on the mechanisms leading to aging and disease.

Current Methods
For the targeted analysis of methylation for specific regions, the gold standard technique is bisulfite sequencing using automated capillary electrophoresis instruments. Measuring genome-wide DNA methylation, however, is only feasible using other techniques, such as restriction landmark genomic scanning, which involves labeling DNA with radioactive phosphorus 32.

Methylation Analysis and the SOLiD™ System
The SOLiD™ System provides a high-throughput method for analyzing genome-wide DNA methylation with a much higher level of resolution than traditional methods.