The fusion of the Breakpoint Cluster Region (BCR) and Abelson Tyrosine-Protein Kinase 1 (ABL1) genes resulting from the translocation generates the chimeric oncogene BCR::ABL1 that is both necessary and sufficient for the development of CML [2,3,4,5,6,7,8,9]. This evidence concerns the gene BCR and chronic myelogenous leukemia, BCR-ABL1 positive.