
What Is DNA Methylation
DNA methylation is a major epigenetic modification involving the addition of a methyl group to the 5 position of cytosine by DNA methyltransferase to form 5-methylcytosine (5-mC). This epigenetic mark has the power to turn genes on or off and can be inherited through cell division. DNA methylation was the first epigenetic mark to be discovered and it plays an important role in normal human development, aging, tumorigenesis, and other genetic and epigenetic diseases.