title: Interleukin-18 promoter -607 C/A and -137 G/C polymorphisms and susceptibility to type 1 diabetes: A meta-analysis.
abstract: OBJECTIVE
  The aim of this study was to determine whether the functional interleukin-18 (IL-18) promoter -607 C/A (rs1946518) and -137 G/C (rs187238) polymorphisms are associated with susceptibility to type 1 diabetes (TID).
  
  
  METHODS
  A meta-analysis was conducted to assess the associations between the IL-18 -607 C/A and -137 G/C polymorphisms and T1D in overall and by ethnic group.
  
  
  RESULTS
  A total of 6075 cases and 5744 controls from ten studies were considered in this meta-analysis. In all study subjects, the meta-analysis showed no association between T1D and the IL-18 -607 C allele (OR=1.083, 95% CI=0.930-1.260, p=0.307). However, stratification by ethnicity indicated an association between the IL-18 -607 C allele and T1D in Asians (OR=1.506, 95% CI=1.172-1.936, p=0.001), but not in Europeans (OR=0.988, 95% CI=0.808-1.209, p=0.907). Analysis using recessive and dominant models and homozygote contrast showed the same -607 C allele pattern in Asians and Europeans. Meta-analysis of the IL-18 -137 G/C polymorphism showed no association between T1D and the IL-18 -137 G allele in all study subjects (OR=1.066, 95% CI=0.926-1.2289, p=0.375). Stratification by ethnicity indicated no association between the IL-18 -137 G allele and T1D in Europeans and Asians (OR=1.021, 95% CI=0.961-1.085, p=0.504; OR=0.851, 95% CI=0.5821-1.245, p=0.406).
  
  
  CONCLUSIONS
  Our meta-analysis demonstrates that the IL-18 -607 C/A polymorphism may be associated with susceptibility to T1D in Asians, but not in Europeans.
authors.affiliation: Division of Rheumatology, Department of Internal Medicine, Korea University College of Medicine, Seoul, Korea. Electronic address: lyhcgh@korea.ac.kr.
authors.forename: Young Ho
authors.initials: YH
authors.lastname: Lee
authors.affiliation: Division of Rheumatology, Department of Internal Medicine, Korea University College of Medicine, Seoul, Korea.
authors.forename: Jae-Hoon
authors.initials: JH
authors.lastname: Kim
authors.affiliation: Division of Rheumatology, Department of Internal Medicine, Korea University College of Medicine, Seoul, Korea.
authors.forename: Gwan Gyu
authors.initials: GG
authors.lastname: Song
mesh_terms: D000483:Alleles; D003922:Diabetes Mellitus, Type 1 / Q000235:genetics*; D056726:Genetic Association Studies; D020022:Genetic Predisposition to Disease; D005838:Genotype; D006801:Humans; D020382:Interleukin-18 / Q000235:genetics*; D016017:Odds Ratio; D020641:Polymorphism, Single Nucleotide; D011401:Promoter Regions, Genetic; D017594:Publication Bias
chemical_list: D020382:Interleukin-18
keywords: Interleukin-18; Meta-analysis; Polymorphism; Type 1 diabetes