1. Gastroenterology Department, Hospital Universitario de Galdakao, 48960 Galdakao, Spain
2. Biocruces Bizkaia Health Research Institute, 48960 Galdakao, Spain
3. Deusto University, 48007 Bilbao, Spain
4. Gastroenterology, Western General Hospital, Edinburgh EH4 2XU, UK
5. Integrative Genomics Lab, Center for Cooperative Research in Biosciences (CIC bioGUNE), Basque Research and Technology Alliance (BRTA), Bizkaia Technology Park, 48160 Derio, Spain
6. IKERBASQUE, Basque Foundation for Sciences, 48009 Bilbao, Spain
7. Gastroenterology Department, Hospital Clínico Universitario de Santiago, 15706 Santiago de Compostela, Spain
8. Gastroenterology Department, St George’s University of London, London SW17 0RE, UK