Decitabine, a methyl cytosine analogue (5-aza-2’-deoxycytidine, 5-Aza-CdR), is an example of a DNMT inhibiting drug used in the therapy of myelodysplastic syndrome (MDS) and acute myeloid leukemia (AML). The gene discussed is DNMT1; the disease is myelodysplastic syndrome.