There are at least 80 known KMT2A fusion partners, but most fusions involve t(11;19)(q23;p13.3) MLLT1, t(9;11)(p21;q23) MLLT3, and t(4;11)(q21;q23) AFF1 in B-ALL. The gene discussed is KMT2A; the disease is acute lymphoblastic leukemia.