KMT2A and acute myeloid leukemia: Indeed, KMT2A-rearranged AML tends to have a maturing myeloid phenotype (M4 and M5 in the French–American–British classification) (Tien et al. 2000), and, in normal hematopoiesis, expression of IRF8 is highest in granulocyte–monocyte progenitors (Supplemental Fig. S13).