title: Associations of interleukin-4 receptor gene polymorphisms (Q551R, I50V) with rheumatoid arthritis: evidence from a meta-analysis.
abstract: OBJECTIVE
  Published data on the associations between interleukin-4 receptor (IL-4R) gene polymorphisms (Q551R, I50V) and rheumatoid arthritis (RA) risk are controversial. To quantitatively evaluate the relationships, a meta-analysis was performed.
  
  
  METHODS
  Studies were identified from the databases of PubMed, MEDLINE, Chinese Biomedical Literature Database, and Chinese National Knowledge Infrastructure, with the last report up to June 2012. The effect summary odds ratio (OR) and 95% confidence interval (CI) were obtained.
  
  
  RESULTS
  A total of six separate comparisons involving 2173 patients and 1892 controls were included to assess the association of IL-4R gene Q551R polymorphism and RA susceptibility. Overall, no significantly elevated RA risk was found in the meta-analysis. The pooled OR for the minor R allele was 0.942 (95% CI: 0.848-1.047, p=0.268) in patients with RA. After stratification by ethnicity, there was still no significant association detected in the European population (OR=0.979, 95% CI: 0.875-1.094). As for I50V polymorphism, there were four comparisons involving 1653 patients and 1584 controls in this meta-analysis. The pooled OR for the V allele was 1.104 (95% CI: 1.001-1.217) in RA, the V allele of the IL-4R gene I50V variant might be a risk factor for RA. However, the relationship between the V allele of IL-4R gene I50V polymorphism and rheumatoid factor positive in patients with RA was not identified through a minor meta-analysis, including four independent relevant comparisons.
  
  
  CONCLUSIONS
  This meta-analysis indicates that the I50V polymorphism of IL-4R gene may confer susceptibility to RA; up to now, there is still not enough evidence to reveal the association of the IL-4R gene Q551R polymorphism with RA risk.
authors: 1 Department of Epidemiology and Biostatistics, School of Public Health, Anhui Medical University , Hefei, People's Republic of China .
authors: Hui
authors: H
authors: Peng
authors: Wei
authors: W
authors: Wang
authors: Mo
authors: M
authors: Zhou
authors: Cai-Yun
authors: CY
authors: Liu
authors: Rui
authors: R
authors: Li
authors: Peng-Fei
authors: PF
authors: Wen
authors: Li-Juan
authors: LJ
authors: Qiu
authors: Hai-Feng
authors: HF
authors: Pan
authors: Dong-Qing
authors: DQ
authors: Ye
mesh_terms: D000483:Alleles; D001172:Arthritis, Rheumatoid / Q000235:genetics*; D005260:Female; D020022:Genetic Predisposition to Disease; D006801:Humans; D053662:Interleukin-4 Receptor alpha Subunit / Q000235:genetics*; D008297:Male; D039781:PubMed; D012217:Rheumatoid Factor / Q000235:genetics
chemical_list: C504000:IL4R protein, human; D053662:Interleukin-4 Receptor alpha Subunit; D012217:Rheumatoid Factor