This large dataset enabled formal delineation of a 7.8 Mb common region of amplification harboring 71 genes, 43 of which were differentially expressed compared with non-iAMP21-ALL, including multiple genes implicated in the pathogenesis of acute leukemia such as DYRK1A, CHAF1B, ERG, HMGN1, and RUNX1. This evidence concerns the gene RUNX1 and acute lymphoblastic leukemia.