1. Edinburgh Inflammatory Bowel Disease Unit, Western General Hospital, NHS Lothian, Edinburgh EH4 2XU, UK
2. Edinburgh Pathology, Centre for Comparative Pathology, Cancer Research UK Scotland Centre, Institute of Cancer and Genetics, University of Edinburgh, Crewe Road, Edinburgh EH4 2XU, UK
3. Edinburgh Colorectal Unit, Western General Hospital, NHS Lothian, Edinburgh EH4 2XU, UK
4. Department of Pathology, Western General Hospital, NHS Lothian, Edinburgh EH4 2XU, UK
5. European Molecular Biology Laboratory, European Bioinformatics Institute, EMBL-EBI, Hinxton, Cambridge CB10 1SD, UK
6. Experimental Cancer Genetics, Wellcome Sanger Institute, Hinxton, Cambridge CB10 1SA, UK
7. Department of Computer Science, School of Mathematical and Computer Sciences, Heriot-Watt University, Edinburgh EH14 4AS, UK