Transduction of WT and Fancc^−/− CD117⁺ cells with FV vectors. (A,B) Light and dark field microscopy of a transduced EGFP-positive progenitor. (C) Transduction efficiency of progenitors cultured from CD117⁺Fancc^−/− and WT cells following FV transduction with the indicated constructs. Data shown are mean transduction efficiency and error bars represent standard error of the mean of 3 replicate dishes. The number of colonies ranged from 90 to 120 per dish. Data are representative of 4 independent experiments with similar results.