Other cytogenetic subgroups in which CDKN2A/B deletions are more prevalent in BCP-ALL are the Philadelphia chromosome (Ph)-positive (Ph+) [23,24,25,26,27], the Ph-like [25,27,28,29], the IGH-ID4 [30] and the PAX5 P80R [31,32] subtypes. The gene discussed is CDKN2A; the disease is acute lymphoblastic leukemia.