Targeting BCR-ABL- transfected cell lines and murine CML models with a variety of tyrosine kinase inhibitors (TKI) has led to a landmark discovery of a novel BCR-ABL targeting drug, imatinib, which subsequently entered clinical trials, showed significant clinical benefits and has become a standard of care for CML patients worldwide [1,3-5]. The gene discussed is ABL1; the disease is chronic myelogenous leukemia, BCR-ABL1 positive.