Instead, IKZF2/Helios loss at 2q34 is the most recurrent alteration involving genes associated with B-cell differentiation (53% in children and 36% in adults), being much more frequently observed in low-hypodiploid B-ALL than in any other B-ALL subtype, including near-haploid ALL (Table 4). The gene discussed is IKZF2; the disease is precursor B-cell acute lymphoblastic leukemia.