CREBBP and precursor B-cell acute lymphoblastic leukemia: Near haploidy (24–30 chromosomes), observed in ~2% of childhood B-ALL cases, associates with Ras mutations (71% of cases), NF1 (44%), histone modifiers (64%), mainly CREBBP (32%), CDKN2A/B (20%), the 6p22 histone gene cluster (19%), IKZF3 (13%), and PAG1 (10%).