[1] Kings Coll London, Inst Liver Studies, Div Transplantat Immunol & Mucosal Biol, London WC2R 2LS, England
[2] Kings Coll Hosp London, Pediat Liver GI & Nutr Ctr, London, England
[3] Univ Calif San Francisco, Dept Med, Liver Ctr Lab, San Francisco, CA 94110 USA
[4] Univ Calif San Francisco, Inst Human Genet, San Francisco, CA 94110 USA