1. Cancer Research UK Scotland Centre, Institute of Genetics and Cancer, University of Edinburgh , Edinburgh , UK
2. Department of Colorectal Surgery, Western General Hospital , Edinburgh, Scotland
3. UK Colon Cancer Genetics Group, Medical Research Council Human Genetics Unit, Medical Research Council Institute of Genetics & Cancer, Western General Hospital, The University of Edinburgh , Edinburgh , UK
4. Department of Colorectal Surgery, Western General Hospital , Edinburgh , Scotland