[1] Newcastle Univ, Dept Human Genet, Newcastle Upon Tyne NE1 7RU, Tyne & Wear, England
[2] Univ Copenhagen, Panum Inst, Dept Med Genet, DK-2200 Copenhagen, Denmark
[3] Univ Cape Town, ZA-7925 Cape Town, South Africa
[4] Groote Schuur Hosp, Dept Surg, ZA-7925 Cape Town, South Africa
[5] St Josefs Hosp Bochum Linden, Dept Gen & Visceral Surg, Bochum, Germany
[6] Princess Anne Hosp, Wessex Clin Genet Serv, Southampton, Hants, England
[7] Leeds Inst Mol Med, Epidemiol & Biostat Sect, Leeds, W Yorkshire, England
[8] Human Nutr Res Ctr, Inst Ageing & Hlth, Newcastle Upon Tyne, Tyne & Wear, England
[9] Jyvaskyla Cent Hosp, Dept Surg, Jyvaskyla, Finland
[10] Royal Melbourne Hosp, Dept Colorectal Med & Genet, Melbourne, Vic, Australia