Due to the fact that the murine in vivo studies so far have not been performed in a chronic-phase CML model under steady-state conditions, our aim was to study the hematopoietic effects of dasatinib (20 mg/kg p.o.)in BCR-ABL expressing SCLtTAxBCR-ABL double transgenic (dtg) mice. The gene discussed is ABL1; the disease is chronic myelogenous leukemia, BCR-ABL1 positive.