A number of the most common mutations in AML occur in genes involved in epigenetic gene regulation, and several of them have been reported as early key events during leukemogenesis8, including ones affecting DNMT3A, isocitrate dehydrogenase 1 and 2 (IDH1 and 2), and chromatin modifiers such as ASXL1. Mutations in these genes that lead to epigenetic changes are also frequently seen in other hematological disorders such as myelodysplastic syndromes (MDS), as well as in solid tumors, including colorectal cancer and brain tumors9–11. The gene discussed is DNMT3A; the disease is myelodysplastic syndrome.