Ph-like ALL is similar to BCR-ABL1 ALL in gene expression profile but lacks BCR-ABL1 fusion protein expressed from the t(9;22) (q34; q11.2). Ph-like ALL with IKZF1 alteration has an inferior five-year EFS as compared to Ph-like ALL with no IKZF1 alteration. This evidence concerns the gene ABL1 and acute lymphoblastic leukemia.