DNMT3A mutations were more frequently detected in ETP-ALL (23.1% vs. 5.3%, P = 0.016), whereas deletions of the CDKN2A, CDKN2B, and MTAP genes located on 9p21 were more commonly noted in non-ETP-ALL (11.5% vs. 55.3%, 7.7% vs. 47.4%, and 7.7% vs. 31.6%, respectively; P < 0.001, P < 0.001, and P = 0.016, respectively). This evidence concerns the gene CDKN2B and acute lymphoblastic leukemia.