title: rs2476601 polymorphism inPTPN22is associated with Crohn's disease but not with ulcerative colitis: a meta-analysis of 16,838 cases and 13,356 controls.
abstract: BACKGROUND
  Although the rs2476601 polymorphism ofPTPN22has been reported to be a susceptibility gene for Crohn's disease (CD), results from different studies vary and remain inconclusive. Also, no association has been found between rs2476601 and the risk of ulcerative colitis (UC). The aim of this meta-analysis was to investigate the association between thisPTPN22polymorphism (rs2476601) and the risk of inflammatory bowel disease, UC and CD.
  
  
  METHODS
  We performed a meta-analysis by identifying relevant candidate gene-based studies from EMBASE and MEDLINE. Odds ratios (OR) and 95% confidence intervals (CI) were calculated to estimate the strength of associations between rs2476601 and inflammatory bowel diseases, using a fixed effect or random effect model. Publication bias was also assessed.
  
  
  RESULTS
  By pooling 14 different studies, 13,356 controls, 8182 patients with CD, and 8656 with UC were included. We found that the T allele ofPTPN22was not significantly associated with a higher risk of developing UC (OR 1.06, 95%CI 0.98-1.14) but was associated with a decreased risk of developing CD (OR 1.28, 95%CI 1.17-1.40). The T allele in rs2476601 lowered the risk of CD by 22%.
  
  
  CONCLUSIONS
  This study shows thatPTPN22(rs2476601) is significantly associated with the risk of developing CD, but has no association with UC. This suggests that these diseases have different pathways involved in their pathophysiology.
authors.affiliation: Gastro-entérologie, Centre Hospitalier Régional Universitaire de Besançon, Besançon (Abdellah Hedjoudje, Clément Briquez, Stéphane Koch, Lucine Vuitton); Faculté de Médecine, Université Paris Descartes, Paris (Chérifa Cheurfa).
authors.forename: Abdellah
authors.initials: A
authors.lastname: Hedjoudje
authors.affiliation: Faculté de Médecine, Université Paris Descartes, Paris (Chérifa Cheurfa); Anésthésie réanimation, CHU Charles Nicolle, Rouen, France (Chérifa Cheurfa).
authors.forename: Chérifa
authors.initials: C
authors.lastname: Cheurfa
authors.affiliation: Gastro-entérologie, Centre Hospitalier Régional Universitaire de Besançon, Besançon (Abdellah Hedjoudje, Clément Briquez, Stéphane Koch, Lucine Vuitton).
authors.forename: Clément
authors.initials: C
authors.lastname: Briquez
authors.affiliation: Johns Hopkins University Evidence-based Practice Center, Johns Hopkins University, Baltimore, United States (Allen Zhang).
authors.forename: Allen
authors.initials: A
authors.lastname: Zhang
authors.affiliation: Gastro-entérologie, Centre Hospitalier Régional Universitaire de Besançon, Besançon (Abdellah Hedjoudje, Clément Briquez, Stéphane Koch, Lucine Vuitton).
authors.forename: Stéphane
authors.initials: S
authors.lastname: Koch
authors.affiliation: Gastro-entérologie, Centre Hospitalier Régional Universitaire de Besançon, Besançon (Abdellah Hedjoudje, Clément Briquez, Stéphane Koch, Lucine Vuitton).
authors.forename: Lucine
authors.initials: L
authors.lastname: Vuitton
keywords: Meta-analysis; PTPN22; candidate gene study; inflammatory bowel disease; polymorphism