Reduced factor-independent growth of single BCR-ABL–transduced SHIP^–/– Sca1⁺lin^–GFP⁺ cells in vitro. (A) Percentage of transduced cells generating clones of more than 2 refractile cells after 7 days in the presence or absence of added growth factors. Values shown are the mean ± SEM from 3 experiments with each genotype of BM cells. *Indicates significantly different from BCR-ABL–transduced +/+ cells (P < .05). (B) Clone size distributions obtained from MIG– or BCR-ABL–transduced SHIP^–/– cells compared with MIG– or BCR-ABL–transduced+/+ cells after being cultured for 7 days in the presence or absence of growth factors. Data for a representative experiment of 3 performed are shown.