DNA methylation is a broadly observed epigenetic modification in living systems, playing diverse functions in transcriptional regulation, transposable element silencing, as well as innate immunity. A nucleosome composed of DNA (gray) and histones (blue) with a single hemimethylated cytosine bound by CDCA7 (purple). Image credit: Kyohei Arita / Yiming Niu. DNA methylation is a process in which a methyl group is attached to the cytosine base of the...
