A significant decrease in human CD45 expression in the bone marrow was observed in the Ptbp2-KO-KCL22 mice compared to the KCL22-NTC mice, indicating that PTBP2 may play a role in the enhanced engraftment of CML cells. The gene discussed is PTBP2; the disease is chronic myelogenous leukemia, BCR-ABL1 positive.