SCLtTA/BCR-ABL mice have increased clonogenic progenitor cells in the spleen but not in the bone marrow. Numbers of CFU-GM (▪) and BFU-E (□) (mean ± SD) were assessed per 20 000 cells extracted from the bone marrow (BM) (upper panel) or spleen (lower panel) on days 42 and 30 after induction of 2 induced double-transgenic mice (dTG) (W185 and W202, respectively) or 2 control mice (wild-type or BCR-ABL single-transgenic, as indicated). Differences of CFU-GM and BFU-E between SCLtTA/BCR-ABL and control mice were statistically significant (P < .05).