ABL kinase (Abelson tyrosine-protein kinase) family includes ABL1 and ARG (ABL2). ABL is said to be deeply involved in chronic myelocytic leukemia (CML) through becoming BCR-ABL fusion gene due to genetic abnormality caused by chromosomal translocation. Imatinib Mesylate (Product No. I0936), which inhibits tyrosine kinase activity of BCR-ABL protein has been used as therapeutic agent for CML).