[1] St James Hosp, Trinity Ctr Hlth Sci, Dept Clin Med, Dublin 8, Ireland
[2] St James Hosp, Inst Mol Med, Dublin Mol Med Ctr, Dublin 8, Ireland
[3] Trinity Coll Dublin, St James Hosp, Dublin, Ireland
[4] St Vincents Hosp, Dept Gastroenterol, Dublin 4, Ireland
[5] Adelaide & Meath Incorporating Natl Childrens Hos, Trinity Ctr Hlth Sci, Dept Clin Med, Dublin, Ireland
[6] Karolinska Inst, Dept Med Nutr, Huddinge, Sweden