Among the recurrent 11q23/KMT2A rearrangements in acute myeloid leukemia (AML), the most common is t(9;11)(p22;q23), which results in a fusion of KMT2A with the MLLT3 gene (KMT2A-MLLT3, previously known as MLL/AF9). The gene discussed is KMT2A; the disease is acute myeloid leukemia.