ABL1 and chronic myelogenous leukemia, BCR-ABL1 positive: The P210 BCR-ABL1 variant expresses in about 48% of Ph+ CML cases, while 52% co-express P210 BCR-ABL1 and P190 BCR-ABL1 variants.7 Approximately 50% of CML patients present without symptoms and are diagnosed incidentally after routine laboratory tests.8 Cytogenetics is the standard diagnostic tool of CML; the Ph chromosome is detected in 90% of the cases.