Chronic myelogenous leukemia (CML) is a hematopoietic disorder of multipotential stem cells, hallmarked by the cytogenetic event t(9;22)(q34;q11), and results in the generation of the Philadelphia (Ph) chromosome carrying BCR-ABL1 fusion gene, which plays a central role in the pathogenesis of CML (1–3). This evidence concerns the gene BCR and chronic myelogenous leukemia, BCR-ABL1 positive.