[1] UCL, Inst Canc, Dept Haematol, London WC1E 6BT, England
[2] Royal Free Natl Hlth Serv NHS Trust, Katharine Dormandy Haemophilia Ctr, London, England
[3] Royal Free Natl Hlth Serv NHS Trust, Thrombosis Unit, London, England
[4] Royal Free Natl Hlth Serv NHS Trust, Liver Unit, London, England
[5] NHS Blood & Transplant, London, England
[6] Barts & London Queen Marys Sch Med & Dent, Ctr Haematol, London, England
[7] Basingstoke & N Hampshire NHS Fdn Trust, Basingstoke, Hants, England
[8] Stanford Univ, Sch Med, Palo Alto, CA 94304 USA
[9] St Jude Childrens Hosp, Dept Surg, Memphis, TN 38105 USA
[10] St Jude Childrens Hosp, Dept Biostat, Memphis, TN 38105 USA
[11] St Jude Childrens Hosp, Dept Hematol, Memphis, TN 38105 USA
[12] Childrens GMP, Memphis, TN USA
[13] Univ Chicago, Dept Pediat, Chicago, IL 60637 USA
[14] Childrens Hosp Philadelphia, Ctr Cellular & Mol Therapeut, Philadelphia, PA 19104 USA
[15] Howard Hughes Med Inst, Chevy Chase, MD USA