| abstract |
DNA methylation (DNAm) based biomarkers of aging have been developed for many tissues and organs. However, these biomarkers have sub-optimal accuracy in skin cells, fibroblasts and other cell types that are often used in ex vivo studies. To address this challenge, we analyzed DNA methylation array data sets derived from multiple sources of DNA, from which we developed a novel and highly robust DNAm age estimator (based on 391 CpGs) for human fibroblasts, keratinocytes, buccal cells, endothelial cells, lymphoblastoid cells, skin, blood, and saliva samples. The application of this new age estimator to ex vivo cell culture systems revealed that cellular population doubling is generally accompanied by an increase in epigenetic aging. The new skin & blood clock disclosed herein is useful for ex vivo and in vivo studies of human aging. |