So far, the most widely studied DNMT inhibitors (DNMTi) 5-azacytidine (azacitidine, Vidaza) and 5-aza-2′-deoxycytidine (5-AZA-CdR, Decitabine, Dacogen) have undergone intensive clinical development that led to their Food and Drug Administration (FDA) approval for patients affected by MDS [99]. Here, DNMT1 is linked to myelodysplastic syndrome.