Our results are in keeping with a previous report and suggest that the TRAF1/C5 region is associated with risk of development of radiological erosions in IP/RA patients.
In particular, recent discoveries highlight the importance of the CD40/NF-kappaB signaling pathway in RA, based on genetic association with several genes relevant to this pathway, including CD40, TRAF1, TNFAIP3, and REL.
Meta-analysis showed a weak association between TRAF1/C5 rs10818488 polymorphism and RA in all subjects (OR = 1.13, 95 % CI = 1.01–1.27, P heterogeneity < 0.001).
We found that mutated allele A or genotypes A/A and G/A of the TRAF1/C5 rs10818488 SNP were more common in individuals with RA than in control individuals (odds ratio [OR]=1.7, 95% confidence interval [CI]=1.35-2.15, and OR=2.22, 95% CI=1.61-3.05, respectively).
This meta-analysis confirms that the TRAF1-C5 rs10818488, rs3761847, rs2900180 and rs10760130 polymorphisms are associated with RA susceptibility in Europeans.
Based on functional data in mice, we hypothesized that the immune-related genes complement component 5 (C5) and/or TNF receptor-associated factor 1 (TRAF1), located on Chromosome 9q33-34, would represent relevant candidate genes for RA.
A real data application to detect the association between gene TRAF1-C5 and rheumatoid arthritis further shows good performance of the proposed procedure.
Taken together, our study demonstrates that the TRAF1/C5 polymorphism (rs10818488) may confer susceptibility to RA in North Africa population, and in European population, it might be a contributory factor towards SLE.
A novel association with a 100-kb region on chromosome 9 that contains the tumor necrosis factor receptor-associated factor 1 (TRAF1) and C5 genes has been observed in some autoimmune rheumatic diseases, in particular in rheumatoid arthritis.
STAT4 rs7574865T allele disclosed a significant influence on the risk of developing SLE (P=0.0005; OR 1.62, 95% CI 1.22-2.16) and RA (P=0.008; OR 1.36; 95% CI 1.08-1.71), whereas no effect on these autoimmune diseases was observed for the TRAF1/C5 polymorphisms examined.
The minor allele for RA susceptibility, rs3761847 SNP in TRAF1/C5 region, was associated with a poor response in linear and logistic univariate and multivariate regression analyses.
Sixty-three RA patients were included.Nine genes (13 SNPs) were subsequently analyzed, including those coding for cytokines involved in synovitis (IL10, LTA, TGFβ1, TNF-α, TNF receptor II) and genes associated with RA susceptibility (-C5 TRAF1, STAT4, TNFAIP3 and PTPN22).
Genome wide association studies have identified an association between SNPs in the 5' untranslated region of the TRAF1 gene with increased incidence and severity of rheumatoid arthritis and other rheumatic diseases.
Association of TRAF1-C5 locus with RA susceptibility was detected in the Japanese populations with modest magnitude, while no significant association was observed for SLE.