BCR and chronic myelogenous leukemia, BCR-ABL1 positive: Chronic Myeloid Leukemia (CML) is a myeloproliferative neoplasm resulting from the BCR-ABL fusion protein coded by the Philadelphia chromosome which results from a reciprocal translocation between theAbelson murine leukemia gene (ABL) on chromosome 9 andBreakpoint Cluster Regiongene (BCR) on chromosome 22 (Jabbour and Kantarjian 2018, Nowell and Hungerford 1960, Rowley 1973).