KMT2A and acute lymphoblastic leukemia: For example, fusions involving the mixed lineage leukemia (MLL)/ histone-lysine N-methyltransferase 2A (KMT2A) gene in acute lymphoblastic leukemia (ALL) and AML produce diverse amino acid sequences among patients because the fusions may occur at multiple breakpoints in the MLL/KMT2A genes and with multiple (>100) partner genes (89, 90).