Although lack of the investigation on IK6 expression in BCR-ABL1-negative B-ALL, according to references, the frequency of all abnormal IKZF1 isoforms is around 15% in BCR-ABL1-negative B-ALL [9,15,16], we believe that IK6 is highly expressed in BCR-ABL1-positive B-ALL based on all the facts. This evidence concerns the gene IKZF1 and precursor B-cell acute lymphoblastic leukemia.