The mixed-lineage leukemia 1 (MLL1) gene (lysine [K]-specific methyl transferase 2A (KMT2A)) located on chromosome 11q23 is disrupted in acute myeloid leukemias (AML), with more than 80 different KMT2A fusion partner genes described to date. Here, KMT2A is linked to acute myeloid leukemia.