Venn diagram having the number of age-dependent methylated loci/genes between brain, kidney and lung. (A) Of 89 age-dependent methylated loci (CpG sites), only four loci were common to different tissues. (B) Similarly, of the 75 associated genes in the 89 age-dependent methylated loci, only four genes were common to different tissues. Most age-dependent differentially methylated regions (aDMRs) were specific for one tissue, with 24 such loci identified in brain, 11 in kidney and 25 in lung. DMGs = differentially methylated genes. ↑ = Hypermethylated; ↓ = Hypomethylated.