Detection of 5-hydroxymethylcytosine by glycosylation

A method for detecting 5-hydroxymethylcytosine in a mammalian nucleic acid, the method comprising:

• contacting a sample comprising said mammalian nucleic acid with an enzyme that utilizes a labeled glucose or a labeled glucose-derivative donor substrate to add a labeled glucose molecule or a labeled glucose-derivative to a 5-hydroxymethylcytosine nucleic acid residue to generate a labeled glucosylated-5-hydroxymethylcytosine,
• wherein the enzyme is a beta-glucosyltransferase and
• wherein the labeled glucose or the labeled glucose-derivative donor substrate comprises a uridine diphosphate glucose (UDPG);
• and treating the contacted sample with a TET enzyme or a catalytically active fragment thereof comprising SEQ ID NO:
• 1.