BACKGROUND AND AIMS: Both genetic and environmental factors play a role in the development of Crohn's disease (CD) and ulcerative colitis (UC), collectively known as inflammatory bowel disease (IBD). The aim of this study was to estimate the genetic component in IBD in Iceland. METHODS: A population-based sample, representing everyone diagnosed with IBD in Iceland from 1950 to 1996, was studied using a computerized population-wide genealogic database. The relationships among the patients were analyzed by calculating the kinship coefficient and the relative risk. RESULTS: The kinship coefficients for the patients were significantly greater than the mean kinship coefficient for the controls ( P < 10 -6 ). The risk ratio for siblings of IBD, UC, and CD patients was 5.0 ( P < 0.001), 5.9 ( P < 0.001), and 4.1 ( P = 0.033), respectively. The cross-risk ratio for siblings of UC patients developing CD (or vice versa) was 2.6 ( P = 0.015). CONCLUSIONS: The results indicate that the IBD patients are more closely related than the controls, which strongly supports the involvement of a genetic component in the development of IBD in Icelandic patients. We find that the increase in risk for relatives of UC probands to develop UC, or relatives of CD probands to develop CD, is greater than the increase in risk for relatives of UC probands to develop CD, or relatives of CD probands to develop UC.
BACKGROUND AND AIMS: Both genetic and environmental factors play a role in the development of Crohn's disease (CD) and ulcerative colitis (UC), collectively known as inflammatory bowel disease (IBD). The aim of this study was to estimate the genetic component in IBD in Iceland. METHODS: A population-based sample, representing everyone diagnosed with IBD in Iceland from 1950 to 1996, was studied using a computerized population-wide genealogic database. The relationships among the patients were analyzed by calculating the kinship coefficient and the relative risk. RESULTS: The kinship coefficients for the patients were significantly greater than the mean kinship coefficient for the controls ( P < 10 -6 ). The risk ratio for siblings of IBD, UC, and CDpatients was 5.0 ( P < 0.001), 5.9 ( P < 0.001), and 4.1 ( P = 0.033), respectively. The cross-risk ratio for siblings of UC patients developing CD (or vice versa) was 2.6 ( P = 0.015). CONCLUSIONS: The results indicate that the IBD patients are more closely related than the controls, which strongly supports the involvement of a genetic component in the development of IBD in Icelandic patients. We find that the increase in risk for relatives of UC probands to develop UC, or relatives of CD probands to develop CD, is greater than the increase in risk for relatives of UC probands to develop CD, or relatives of CD probands to develop UC.
Authors: Gian Eugenio Tontini; Maurizio Vecchi; Luca Pastorelli; Markus F Neurath; Helmut Neumann Journal: World J Gastroenterol Date: 2015-01-07 Impact factor: 5.742
Authors: Sigurgeir Olafsson; Pernilla Stridh; Steffan Daniël Bos; Andres Ingason; Jack Euesden; Patrick Sulem; Gudmar Thorleifsson; Omar Gustafsson; Ari Johannesson; Arni J Geirsson; Arni V Thorsson; Bardur Sigurgeirsson; Bjorn Runar Ludviksson; Elias Olafsson; Helga Kristjansdottir; Jon G Jonasson; Jon Hjaltalin Olafsson; Kjartan B Orvar; Rafn Benediktsson; Ragnar Bjarnason; Sjofn Kristjansdottir; Thorarinn Gislason; Trausti Valdimarsson; Evgenia Mikaelsdottir; Snaevar Sigurdsson; Stefan Jonsson; Thorunn Rafnar; Dag Aarsland; Srdjan Djurovic; Tormod Fladby; Gun Peggy Knudsen; Elisabeth G Celius; Kjell-Morten Myhr; Gerdur Grondal; Kristjan Steinsson; Helgi Valdimarsson; Sigurdur Bjornsson; Unnur S Bjornsdottir; Einar S Bjornsson; Bjorn Nilsson; Ole A Andreassen; Lars Alfredsson; Jan Hillert; Ingrid Skelton Kockum; Gisli Masson; Unnur Thorsteinsdottir; Daniel F Gudbjartsson; Hreinn Stefansson; Haukur Hjaltason; Hanne F Harbo; Tomas Olsson; Ingileif Jonsdottir; Kari Stefansson Journal: NPJ Genom Med Date: 2017-08-08 Impact factor: 8.617
Authors: Jiun-Sheng Chen; Fulan Hu; Subra Kugathasan; Lynn B Jorde; David Nix; Ann Rutherford; Lee Denson; W Scott Watkins; Sampath Prahalad; Chad Huff; Stephen L Guthery Journal: G3 (Bethesda) Date: 2018-08-30 Impact factor: 3.154
Authors: Mathena Vinayaga-Pavan; Matthew Frampton; Nikolas Pontikos; Adam P Levine; Phillip J Smith; Jon G Jonasson; Einar S Björnsson; Anthony W Segal; Andrew M Smith Journal: Inflamm Bowel Dis Date: 2019-01-10 Impact factor: 5.325