The latest WHO classification has expanded the list of recurrent genetic abnormalities that define AML regardless of blast count: five specific fusions (PML::RARA, RUNX1::RUNX1T1, CBFB::MYH11, DEK::NUP214, and RBM15::MRTFA), three groups of gene rearrangement (KMT2A, MECOM, and NUP98) and one gene mutation (NPM1). The gene discussed is CBFB; the disease is acute myeloid leukemia.