Although the pathogenesis of NPM1m AML is unclear, its typically coexisting mutations are well identified and include FLT3 alterations, mutations in genes coding for Ras-pathway components, and mutations in the epigenetic factors TET2, IDH1/2, and DNMT3A, with the mechanisms of synergy not being well understood [11]. Here, TET2 is linked to acute myeloid leukemia.