Age-specific differentially methylated cytosines.

The percent breakdown of locations for differentially methylated regions [DMCs] as a function of age between young and old brain [left column], between young and old spleen [center column] and an aggregate of all young versus all old samples [N = 12 total in the right column]. The top row delineates between DMCs located at promoters, exons, introns or intergenic regions. The bottom row delineates between DMCs located at CpG islands [CpGi], CpG shores or other regulatory regions (see S1 Table).