This demonstrates a B lineage specific requirement of Src kinases for BRC/ABL1 driven malignancies, and is consistent with synergy of pan Src kinase inhibitor CGP76030 with imatinib mesylate in treating BCR/ABL1-induced B ALL but not CML. The gene discussed is ABL1; the disease is chronic myelogenous leukemia, BCR-ABL1 positive.