Association between polymorphism in STAT4 gene and risk of rheumatoid arthritis: a meta-analysis.

BACKGROUND: Rheumatoid arthritis (RA) is a common chronic inflammatory autoimmune disease, affecting 1% of the population worldwide. Single nucleotide polymorphisms (SNPs) of signal transducer and activator of transcription 4 (STAT4) gene are suspected to have some relationship with the risk of RA. This meta-analysis aimed to evaluate the relationship between the polymorphism rs7574865 in STAT4 gene with RA and also examine whether the associations that have been reported in these studies differ between ethnic groups.
METHODS: We retrieved the relevant articles from PubMed, EMBASE and the China National Knowledge Infrastructure (CNKI) databases. The odds ratios (ORs) and their 95% confidence intervals (95% CIs) associated with the minor T allele of STAT4 rs7574865 SNP were extracted from the published studies and included in the analysis. Meta-analyses were performed on the total data set and separately for the major ethnic groups and RF and anti-CCP status. All analyses were performed using the Stata software.
RESULTS: Twenty-three articles were included in the present analysis. Meta-analysis showed an association between the STAT4 polymorphism and RA in all subjects (OR=1.299, 95%CI=1.230-1.371, P<0.001). Stratified analyses indicated that the STAT4 rs7574865 T allele was significantly associated with RA in both Caucasians and Asians, in both positive and negative RF patients versus controls, also significantly in the presence of anti-CCP, both positive and negative. As for genotypes of rs7574865 polymorphism, all the results were significant, no matter in total subjects or stratified analyses by ethnic groups or by RF and anti-CCP status.
CONCLUSION: Genetic polymorphism rs7574865 in STAT4 gene might be associated with RA susceptibility in total subjects, major ethnic groups and different status of anti-CCP or RF.