Epigenetic chemical probes.

Epigenetic control of gene expression occurs at two distinctlevels: DNA methylation and histone modification. Over thepast 10 years, the discovery of epigenetic targets has acceleratedto the point where more than 400 domains have beenidentified that are involved in either DNA methylation, themodification of histones (and some nonhistones), or translationof these modifications into changes in gene expression