KMT2A and acute lymphoblastic leukemia: Remarkably, a cohort of 26 patients with different chromosomal alterations involving the KMT2A gene has revealed that patients with the t(4;11) translocation, which corresponds to the worst outcome subtype of BCP-ALL, have much more highly hypomethylated enhancer sites than normal BCPs and other KMT2A-rearranged subtypes [57].