title: Association between polymorphism in the promoter region of Interleukin 6 (-174 G/C) and risk of Alzheimer's disease: a meta-analysis.
abstract: Studies of the relationship between Alzheimer's disease (AD) and polymorphism in the promoter region of Interleukin 6 (IL-6) -174 G/C have reported inconsistent results. To assess the association between IL-6 -174 G/C promoter polymorphism and AD risk, a meta-analysis containing 3,101 AD cases and 3,860 controls from 18 case-control studies was performed. There were 16 studies involving Europeans and 2 studies involving non-Europeans. The combined results showed significant differences in recessive model [CC versus GC + GG, odds ratio (OR) = 0.70, 95% confidence interval (CI) = 0.54-0.90] and heterozygote comparison (CC versus GC, OR = 0.76, 95% CI = 0.60-0.96) on the basis of all studies. On subgroup analysis by ethnicity, similarly significant differences in recessive model (CC versus GC + GG) were found in both Europeans and non-Europeans, but significant difference in heterozygote comparison (CC versus GC) was found only in non-Europeans. In conclusion, there were statistically significant differences in genotype distribution of IL-6 -174 G/C between AD cases and controls in recessive model (CC versus GC + GG). Genotype CC of IL-6 -174 G/C could decrease the risk of AD. Further studies with large sample size, especially in subgroup analysis, should be done.
authors: Department of Medical Genetics, College of Basic Medical Science, Third Military Medical University, Gaotanyan St., Shapingba District, Chongqing, 400038, People's Republic of China.
authors: Limeng
authors: L
authors: Dai
authors: Dan
authors: D
authors: Liu
authors: Hong
authors: H
authors: Guo
authors: Yanyan
authors: Y
authors: Wang
authors: Yun
authors: Y
authors: Bai
mesh_terms: D000544:Alzheimer Disease / Q000235:genetics*; D016206:Databases, Bibliographic / Q000706:statistics & numerical data; D005006:Ethnicity / Q000235:genetics; D020022:Genetic Predisposition to Disease; D006801:Humans; D015850:Interleukin-6 / Q000235:genetics*; D020641:Polymorphism, Single Nucleotide / Q000235:genetics*; D011401:Promoter Regions, Genetic / Q000235:genetics*
chemical_list: D015850:Interleukin-6