Ninety-nine patients had normal karyotype; 31 patients had Ph+ ALL as defined by conventional cytogenetics, FISH, or PCR; 15 patients had other unfavorable abnormalities (−7, +8, 11q23/MLL gene rearrangement); and 15 patients had other karyotypic abnormalities. The gene discussed is KMT2A; the disease is acute lymphoblastic leukemia.