[1] Hop Necker Enfants Malad, Paediat Gastroenterol Unit, Dept Pathol, F-75730 Paris, France
[2] Univ Bonn, Childrens Hosp, Ctr Med, D-5300 Bonn, Germany
[3] Univ Washington, Seattle, WA 98195 USA
[4] Childrens Hosp, Reg Med Ctr, Seattle, WA USA
[5] Galliera Hosp, Lab Human Genet, Genoa, Italy
[6] Univ Paris 05, INSERM, Hop Necker Enfants Malad, Dept Paediat,Fac Necker, Paris, France