TCF3 and acute lymphoblastic leukemia: Clinically significant CNVs were more common in ALL, the most common of which was -9p or loss of heterozygosity (LOH) of 9p including CDKN2A, CDKN2B, and PAX5. Following were gains of chromosome 21 and 17q including IKZF3, -7p/LOH of 7p including IKZF1, -19p including TCF3, and -17p/LOH including TP53. The most commonly identified variants in leukemia/lymphoma specimens were in NRAS (12.7%, 17/134), including patients with B-ALL [9], acute myelogenous leukemia (AML) [4], JMML [2], T-ALL [1], and T-myeloid leukemia [1] (Fig. 5).