The mutations in AML involve epigenetic modifiers (TET2, IDH1/IDH2, DNMT3A, ASXL1, KMT2A, EZH2), activated signaling pathway (FLT3, KRAS, NRAS, KIT), tumor suppressor genes (TP53, WT1), RNA splicing (SF3B1), nucleophosmin mutation (NPM1), and genes coding for transcription-differentiation (CEBPA, RUNX1) (Figure 1) (6,7,8). Recurrently mutated genes in AML and MDS are listed in Table 1. The gene discussed is TET2; the disease is myelodysplastic syndrome.