title: Associations between CD24 gene polymorphisms and inflammatory bowel disease: A meta-analysis.
abstract: OBJECTIVE
  To evaluate the relationships between CD24 gene polymorphisms and the risk of inflammatory bowel disease (IBD), including ulcerative colitis (UC) and Crohn's disease (CD).
  
  
  METHODS
  The PubMed, Web of Science and Cochrane Library databases were searched (up to May 30, 2014). The search terms "CD24", "inflammatory bowel disease", "Crohn's disease", "Ulcerative colitis", "IBD", "CD" or "UC"; and "polymorphism", "mutation" or "variant" were used. Association studies were limited to the English language, but no limitations in terms of race, ethnicity or geographic area were employed. Stata SE12 software was used to calculate the pooled odds ratios (ORs) with 95% confidence intervals (CIs). P < 0.05 was considered statistically significant. The information was independently extracted from each eligible study by two investigators. Two common polymorphisms, C170T (rs8734) and TG1527del (rs3838646), in the CD24 gene were assessed.
  
  
  RESULTS
  A total of three case-control studies including 2342 IBD patients and 1965 healthy controls were involved in this meta-analysis. The patients and controls were from Caucasian cohorts. The three articles included in this meta-analysis all conformed to Hardy-Weinberg equilibrium. This meta-analysis revealed that there were no significant associations between the two CD24 polymorphisms and the risk for IBD (all P > 0.05). However, in a disease subgroup analysis, we found that the CD24 C170T polymorphism was associated with an increased risk of UC in a dominant model (OR = 1.79, 95%CI: 1.15-2.77, P = 0.009) and an additive model (OR = 1.87, 95%CI: 1.19-2.93, P = 0.007), but this relationship was not present for CD. The CD24 TG1570del polymorphism was significantly associated with CD in the additive model (OR = 1.24, 95%CI: 1.01-1.52, P = 0.037).
  
  
  CONCLUSIONS
  Our findings provide evidence that the CD24 C170T polymorphism might contribute to the susceptibility to UC, and the CD24 TG1527del polymorphism might be associated with the risk of CD.
authors.affiliation: Xiao-Li Huang, Department of Gastroenterology, Gulou School of Clinical Medicine, Nanjing Medical University, Nanjing 210008, Jiangsu Province, China.
authors.forename: Xiao-Li
authors.initials: XL
authors.lastname: Huang
authors.affiliation: Xiao-Li Huang, Department of Gastroenterology, Gulou School of Clinical Medicine, Nanjing Medical University, Nanjing 210008, Jiangsu Province, China.
authors.forename: Dong-Hua
authors.initials: DH
authors.lastname: Xu
authors.affiliation: Xiao-Li Huang, Department of Gastroenterology, Gulou School of Clinical Medicine, Nanjing Medical University, Nanjing 210008, Jiangsu Province, China.
authors.forename: Guo-Pin
authors.initials: GP
authors.lastname: Wang
authors.affiliation: Xiao-Li Huang, Department of Gastroenterology, Gulou School of Clinical Medicine, Nanjing Medical University, Nanjing 210008, Jiangsu Province, China.
authors.forename: Shu
authors.initials: S
authors.lastname: Zhang
authors.affiliation: Xiao-Li Huang, Department of Gastroenterology, Gulou School of Clinical Medicine, Nanjing Medical University, Nanjing 210008, Jiangsu Province, China.
authors.forename: Cheng-Gong
authors.initials: CG
authors.lastname: Yu
mesh_terms: D051927:CD24 Antigen / Q000235:genetics*; D003093:Colitis, Ulcerative / Q000175:diagnosis / Q000235:genetics* / Q000276:immunology; D003424:Crohn Disease / Q000175:diagnosis / Q000235:genetics* / Q000276:immunology; D020022:Genetic Predisposition to Disease; D006801:Humans; D016017:Odds Ratio; D010641:Phenotype; D011110:Polymorphism, Genetic; D011379:Prognosis; D018570:Risk Assessment; D012307:Risk Factors
chemical_list: D051927:CD24 Antigen; C497889:CD24 protein, human
keywords: CD24; Inflammatory bowel disease; Meta-analysis; Polymorphism; rs3838646; rs8734