ABL1 and chronic myelogenous leukemia, BCR-ABL1 positive: P190BCR-ABL has a higher activity than p210BCR-ABL resulting in a greater potential to induce a malignant change.1 Occasional cases with other junctions such as b2a3, b3a3, e1a3, e6a2 or e2a2 have been reported in patients with ALL and CML.4