Association between polymorphism of interleukin-6 gene and multiple sclerosis: a meta-analysis

Abstract

Objective To comprehensively evaluate the association between Interleukin-6 (IL-6)-174 G/C polymorphism and multiple sclerosis (MS).Methods we used literature retrieval in PubMed to search the correlation literatures between-174G/C polymorphism in IL-6 gene promoter region and MS untill October 2012.Odds ratios (OR) with 95 ％ confidence intervals (95 ％ CI) were calculated in fixed or random model,I2 was calculated to examine heterogeneity,and funnel plots were plotted to detect the publication bias with Revman4.2 and Stata10.0.Results A total of 6 articles including 777 MS patients and 1108 healthy controls were selected in the study.There was no evidence of publication bias among these studies.Compared with control groups,the MS patients showed significantly higher frequency of G allele(OR =1.29,95％ CI:1.11 ～ 1.49,P =0.0006) and GG genotype(OR =1.54,95％ CI:1.00 ～ 2.36,P =0.05).However,stratification by ethnicity indicated that CC genotype was significantly decreased in Caucasian population (OR =0.65,95％ CI:0.42 ～ 1.01,P =0.05) and inversed in Iranian population (OR =1.92,95％CI:1.14 ～3.23,P=0.01).Conclusion Our study indicated that IL-6-174G allele and GG genotype may be associated with MS,and the CC genotype has a different association in MS between the Caucasian and Iranian population. Key words: Interleukin-6 ; Multiple sclerosis ; Polymorphism ; Meta-analysis