In B-cell progenitor (BCP) ALL favorable genetic alterations are hyperdiploidy or translocation t(12;21)/ETV6-RUNX1, whereas t(9;22)/BCR-ABL1, KMT2A (MLL) rearrangements, chromosome 21 amplification (iAMP21), t(17/19)/TCF3-HLF and hypodiploidy are associated with poor prognosis. This evidence concerns the gene KMT2A and acute lymphoblastic leukemia.