JAK1 and acute lymphoblastic leukemia: Most previous mutation analyses of T-ALL have focused on only one or a few candidate genes, for example ETV6 (12p13.2), FBXW7 (4q31.3), FLT3 (13q12.2), IL7R (5p13.2), IRS4 (Xq22.3), JAK1 (1p31.3), NOTCH1 (9q34.3), NRAS (1p13.2), and TP53 (17p13.1).