Age-Associated Epigenetic Change in Chimpanzees and Humans

Genome wide DNA methylation profiling of captive chimpanzees of ages spanning the chimpanzee lifespan (whole blood) Methylation levels have been shown to change with age at sites across the human genome. Change at some of these sites is so consistent across individuals that it can be used as an “epigenetic clock” to predict an individual’s chronological age within a few years. Studies of age-related epigenetic change in other mammals, including mice, whales, and canids, show that some but not all of the same loci as in humans undergo age-associated methylation changes. An in-depth comparison of chimpanzees with humans is of interest because the two species are genetically similar but differ in lifespan. To this end, we profiled genome-wide blood methylation levels for 113 samples from 83 chimpanzees aged 1-58 years (26 chimpanzees were sampled at multiple ages during their lifespan). We used this data to build a chimpanzee-specific epigenetic clock model as well as to compare genome-wide patterns of change with age between humans and chimpanzees more generally. Bisulfite convrted DNA for 113 individuals was profiled by the Illumina Infinium EPIC array Please note that all the human data was previously published by others and accessioned to GEO (Accession numbers: GSE40279, GSE87571, GSE56105).