In NK-AML, Bullinger et al. first distinguished two distinct groups: the FAB M1/M2 subtype with FLT3 mutation, in which the GATA2, NOTCH1, DNMT3A and DNMT3B genes are highly expressed, and the FAB M4/M5 subtype, in which the abnormally expressed genes are associated with granulocyte and monocyte differentiation, the immune response, and hematopoietic stem cell survival. The gene discussed is FLT3; the disease is acute myeloid leukemia.