Among the DNMT inhibitors, 5-azacytidine (Azacitidine) and 5-aza-2′-deoxycytidine (Decitabine) have been beneficial for the treatment of acute myelocytic leukemia (AML) and myelodysplastic syndrome (MDS), both of which have been approved by the US FDA [349,350]. The gene discussed is DNMT1; the disease is myelodysplastic syndrome.