ABL1 and chronic myelogenous leukemia, BCR-ABL1 positive: Chronic myeloid leukemia (CML) is a myeloproliferative neoplasm characterized by BCR-ABL fusion gene.[1] A crude annual incidence of CML is 0.7–1.0/100,000 with a median age at diagnosis of 57 to 60 years.[2] Imatinib, a selective BCR-ABL tyrosine kinase inhibitor, has greatly contributed to the improvement of treatment outcome.