title: Polymorphisms in STAT4 and IRF5 increase the risk of systemic sclerosis: a meta-analysis.
abstract: BACKGROUND
  Systemic sclerosis (SSc) is the most severe connective tissue disorder. Recent studies have demonstrated that genetic factors may play a role in the development of SSc. The aim of this study was to investigate the association of signal transducer and activator of transcription 4 (STAT4) rs7574865 and interferon regulatory factor 5 (IRF5) rs2004640 polymorphisms with risk of SSc.
  
  
  METHODS
  Case-control studies were obtained from the electronic database of PubMed, Medline, Embase, and CNKI (China National Knowledge Infrastructure) up to December 2013. The association between STAT4 and IRF5 polymorphisms and SSc susceptibility was assessed by pooled odds ratios (ORs) and 95% confidence intervals (CI).
  
  
  RESULTS
  Six related studies, including 4746 SSc cases and 7399 healthy controls, were pooled in this meta-analysis. For STAT4 polymorphism, we observed a statistically significant positive association between risk factor T allele carriers and SSc susceptibility (OR = 1.37, 95% CI = 1.27-1.48, P < 0.00001) in the overall population. The presence of limited cutaneous (lcSSc) and diffuse cutaneous (dcSSc) scleroderma also showed a significant association with each of the genetic models (P < 0.00001). For IRF5 polymorphism, the T allele was shown to be strongly associated with increased SSc risk (OR = 1.27, 95% CI = 1.17-1.39, P < 0.00001). No significant heterogeneity between studies was found.
  
  
  CONCLUSIONS
  The results demonstrated that STAT4 rs7574865 and IRF5 rs2004640G/T substitution are associated with a susceptibility to SSc, and they may serve as the SSc genetic susceptibility factor. These data confirmed that genetic polymorphisms may play a role in the development of SSc and have provided new insight into the pathogenesis of SSc.
authors.affiliation: Department of Dermatology, General Hospital of Beijing Military Command, Beijing, China.
authors.forename: Yang
authors.initials: Y
authors.lastname: Xu
authors.affiliation: Department of Dermatology, General Hospital of Beijing Military Command, Beijing, China.
authors.forename: Wenling
authors.initials: W
authors.lastname: Wang
authors.affiliation: Department of Dermatology, General Hospital of Beijing Military Command, Beijing, China.
authors.forename: Yanli
authors.initials: Y
authors.lastname: Tian
authors.affiliation: Department of Dermatology, General Hospital of Beijing Military Command, Beijing, China.
authors.forename: Jingyang
authors.initials: J
authors.lastname: Liu
authors.affiliation: Department of Dermatology, General Hospital of Beijing Military Command, Beijing, China.
authors.forename: Rongya
authors.initials: R
authors.lastname: Yang
mesh_terms: D000483:Alleles; D016022:Case-Control Studies; D020022:Genetic Predisposition to Disease / Q000235:genetics*; D006801:Humans; D050835:Interferon Regulatory Factors / Q000235:genetics*; D011110:Polymorphism, Genetic; D012307:Risk Factors; D050797:STAT4 Transcription Factor / Q000235:genetics*; D012595:Scleroderma, Systemic / Q000235:genetics*
chemical_list: C431713:IRF5 protein, human; D050835:Interferon Regulatory Factors; D050797:STAT4 Transcription Factor; C494090:STAT4 protein, human