1 Edinburgh Inflammatory Bowel Diseases Unit, Western General Hospital, Edinburgh EH4 2XU, UK; Institute of Genetics and Cancer, University of Edinburgh, Edinburgh, UK. Electronic address: sdin@ed.ac.uk.
2 Oxford Children's Hospital, Oxford, UK.
3 Wyke Regis and Lanehouse Medical Centre, Weymouth, UK; Dorset Healthcare University Foundation Trust, Dorset, UK.
4 General Practice, Oxford, UK; NB Medical Education, Newcastle upon Tyne, UK.