Chronic myeloid leukemia (CML) is a well-known hematological malignancy that is characterized in most patients by the translocation t (9; 22) (q34; q11), leading to the formation of the Philadelphia chromosome carrying the chimeric oncogene breakpoint cluster region-Abelson (BCR-ABL). The gene discussed is ABL1; the disease is chronic myelogenous leukemia, BCR-ABL1 positive.