CDKN2A and acute lymphoblastic leukemia: Recurrent microdeletions targeting CDKN2A/CDNK2B (22–50%) have been identified in NH ALL [12, 15] and Holmfeldt et al [15] showed that this subtype frequently also harbors mutations and deletions targeting NF1 (44%), IKZF3 (13%), and PAG1 (10%) (Figure 1).