CML, a clonal hematopoietic stem cell disorder, is characterized by the fusion of the Abelson gene (ABL1) on chromosome 9q34 with the breakpoint cluster region (BCR) gene on chromosome 22q11.2, which is known as the Philadelphia translocation [1]. The gene discussed is BCR; the disease is chronic myelogenous leukemia, BCR-ABL1 positive.