Studies by Gangadharan et al. (29) demonstrated that sustained high levels of plasma FVIII were achieved in hemophilia A mice that were preconditioned with either lethal 11 Gy or sub-lethal 5.5 Gy TBI and received Sca-1+ or c-kit+ cells transduced with porcine FVIII driven by the mouse stem cell virus (MSCV) promoter (MSCV-porcine fVIII) using a retrovirus-mediated gene transfer system. The gene discussed is F8; the disease is hemophilia A.