We have previously isolated fetal liver kinase-1-positive (Flk1+) mesenchymal stem cells (MSCs) carrying the BCR/ABL fusion gene from the bone marrow of Philadelphia chromosome-positive (Ph+) patients with hemangioblast property and they were proved to be the cancer stem cells in CML which differ from the normal MSCs4. The gene discussed is BCR; the disease is chronic myelogenous leukemia, BCR-ABL1 positive.