In the international clinical trial of the Medical Research Council (MRC) UKALLXII and the Eastern Cooperative Oncology Group (ECOG) E2993, cytogenetic data from a total of 1522 adult patients with newly diagnosed ALL were centrally reviewed of 1003 cases in which cytogenetic analysis was successfully performed; 69 patients had a translocation involving the MLL gene located at 11q23 and the majority of these (n = 54) had a t(4;11)(q21;q23), with a global estimate incidence of 6.9% and 5.4% respectively [30]. The gene discussed is KMT2A; the disease is acute lymphoblastic leukemia.