On the other hand BCR-ABLp185 is detected in B-ALL leukemia and is rarely found in CML patients.[7] In murine models, over-expression of the respective protein in hematopoietic stem and progenitor cells gives rise to an aggressive myeloproliferative disease (MPD) or leukemia phenotype with very short latency.[8,9] Although development of tyrosine kinase inhibitors (TKI) was a remarkable milestone for the therapy of BCR-ABL positive leukemias, disease persistence and resistance to TKIs are remaining issues. This evidence concerns the gene ABL1 and chronic myelogenous leukemia, BCR-ABL1 positive.