ABL1 and chronic myelogenous leukemia, BCR-ABL1 positive: Chronic myeloid leukemia (CML) is a myeloproliferative disease characterized by the BCR-ABL constitutive tyrosine kinase (TK) oncoprotein, the result of the balanced reciprocal translocation of chromosomes 9 and 22 (t(9;22)(q34;q11)) [1].