Genetics versus environment in inflammatory bowel disease: results of a British twin studyBMJ 1996; 312 doi: https://doi.org/10.1136/bmj.312.7023.95 (Published 13 January 1996) Cite this as: BMJ 1996;312:95
- Nick P Thompson, research fellowa,
- Richard Driscoll, chairmanb,
- Roy E Pounder, professor of medicinea,
- Andrew J Wakefield, directora
- a Inflammatory Bowel Disease Study Group, Royal Free Hospital School of Medicine, London NW3 2PF
- b National Association for Colitis and Crohn's Disease, St Albans, Herts AL1 1AB
- Correspondence to: Mr Wakefield.
- Accepted 8 November 1995
A genetic component to the cause of inflammatory bowel disease has been inferred from the increased risk among first degree relatives (5-20% cumulative incidence).1 The only previous study of inflammatory bowel disease in twins used the Swedish twin registry and a register of hospital inpatients to identify 80 twin pairs.2 The aim of our study was to determine the levels of concordance for inflammatory bowel disease in British twin pairs.
Subjects, methods, and results
The National Association for Colitis and Crohn's Disease is a patient support group with about 16000 members with inflammatory bowel disease. All members were asked to complete and return a prepaid postcard if they had inflammatory bowel disease and were born as one of a twin pair. Those replying were sent a follow up questionnaire to obtain details of the member's diagnosis and twin. Zygosity was determined with a validated questionnaire.3
A report of inflammatory bowel disease in a proband's twin was confirmed …