Tags: Chemical Compound, Chemical Substance.
5-Hydroxymethylcytosine is a DNA pyrimidine nitrogen base. It is formed from the DNA base cytosine by adding a methyl group and then a hydroxy group. It is important in epigenetics because the hydroxymethyl group on the cytosine can possibly switch a gene on and off. It was first seen in bacteriophages in 1952. However in 2009 it was found to be abundant in human and mouse brains as well as in embryonic stem cells.
