5-Hydroxymethylcytosine(5hm C),which was formed from the enzymatic oxidation of 5-methylcytosine(5m C) by TET proteins family,played an important role in gene transcription and expression regulation as a new epigenetic modified in mammal animal. A method for global DNA hydroxymethylation in blood sample of rats using hydrophilic interaction liquid chromatography-tandem mass spectrometry( LC-MS / MS) was developed. Genomic DNA from blood samples was extracted by genomic DNA isolation kit,and then was hydroly...