EPIGENETIC METHYLATION MARKERS. “Both in monocots (rice) and in dicots (Arabidopsis and poplar), CG methylation, but not CHG or CHH methylation, exhibits a peak in the body of protein-coding genes. Exons tend to be more highly methylated than introns, and the end of the gene shows a similar drop in methylation to the gene’s promoter region.”
http://jxb.oxfordjournals.org/content/62/11/3713.full