At both the initiation phase and the TKI-induced remission stage of CML, a small number of BCR-ABL-expressing LSCs are present at one site in bone marrow, where normal hematopoietic cells including hematopoietic stem/progenitor cells (HSPCs) are abundant [62]. This evidence concerns the gene ABL1 and chronic myelogenous leukemia, BCR-ABL1 positive.