We found that DNA hypomethylation was the most discriminate epigenetic feature of any given tissue and that tissue-specific hypomethylated genes were associated with the function of that tissue. Among these genes were transcription factors used for the transdifferentiation of fibroblasts into neurons, master regulators of oligodendrocyte differentiation, and iPSC reprogramming factors. We suggest that the identification of uniquely hypomethylated genes will permit the discovery of high-level regulators of cellular identity, and may inform the selection of factors for novel transdifferentiation protocols.
