1. Centre for Population Health Sciences, University of Edinburgh, Edinburgh EH8 9AG, UK
2. Colon Cancer Genetics Group and Academic Coloproctology, Institute of Genetics and Molecular Medicine, University of Edinburgh and MRC Human Genetics Unit, Western General Hospital, Edinburgh, EH4 2XU, UK
3. Department of Clinical Biochemistry, Royal Infirmary, Glasgow G4 0SF, UK
4. School of Nursing, Midwifery and Social Care, Faculty of Health, Life and Social Sciences, Edinburgh Napier University, Edinburgh, UK
5. Public Health Nutrition Research Group, The Rowett Institute of Nutrition and Health, Bucksburn, Aberdeen AB21 9SB, UK
6. Southeast of Scotland Clinical Genetic Services, University of Edinburgh, Western General Hospital, Edinburgh, EH4 2XU, UK