Finally, transcript quantification of three members of the DNMT family (DNMT1, DNMT3A, and DNMT3B) responsible for the methylation of 5-Cyt to 5-mCyt and of the three members of the TET family (TET1, TET2, and TET3) responsible for the oxidation of 5-mCyt to 5-hmCyt was performed by RTq-PCR in 11 CLL patients from the low-risk group, 13 CLL patients from the intermediate/high-risk group, and 9 healthy controls (Fig. 4). The gene discussed is TET1; the disease is B-cell chronic lymphocytic leukemia.