Oxygenase Catalyzed 5-Methylcytosine Hydroxylation

Recent reports identify the oxygenase catalyzed production of 5-hydroxymethylcytosine as a modification to mammalian DNA (Kriaucionis and Heintz, 2009; Tahiliani et al., 2009). This discovery has potential far-reaching implications for epigenetic regulation and will stimulate efforts to identify new nucleic acid modifications.