A recent study demonstrated that promoter hydroxymethylation of tumor suppressor genes DAPK1, RIZ1, P16INK4A, RASSF1A and p14ARFARF was a characteristic feature of CML disease progression and indicated poor imatinib response and poor overall survival of CML patients to imatinib therapy [22]. This evidence concerns the gene CDKN2A and chronic myelogenous leukemia, BCR-ABL1 positive.