Additionally, somatic alterations in cyclin-dependent kinase inhibitor 2A (CDKN2A), particularly deletions, are highly prevalent in T-cell ALL (T-ALL) and B-cell ALL (B-ALL) cases, occurring in 78% and 42%, respectively, in contrast to solid tumors where they are present in 11% or less of cases [7]. The gene discussed is CDKN2A; the disease is T-cell acute lymphoblastic leukemia.