ABL1 and acute lymphoblastic leukemia: However, no consensus has been reached on the different BCR-ABL1 transcripts in Ph+ ALL, either in clinical characteristics or outcome, which may be related to the following three reasons: (1) the relatively small sample sizes; (2) the heterogeneity of the research objects, which included patients with Ph+ acute myeloid leukemia, acute undifferentiated leukemia, a preceding antecedent of CML, or pediatric population; and (3) the inconsistency in chemotherapy protocols, proportion of allo-HSCT and use of TKIs.