Background: The purposes of this study were to explore whether the Toll-like receptor 4 (TLR4) gene rs7873784 G/C polymorphism was related to the risk of rheumatoid arthritis (RA) and to the clinical features of the disease in Chinese subjects.
Materials and methods: We examined the TLR4 rs7873784 G/C polymorphism in 805 Chinese RA patients and 1095 healthy controls. Genotype was determined with a custom-by-design 48-Plex single nucleotide polymorphism scan™ Kit. Blood plasma levels of TLR4 in 170 RA patients and 170 matched controls were measured by ELISA.
Results: The TLR4 gene rs7873784 G/C polymorphism was related to a reduced risk for RA. By stratified analysis, we found a dramatically reduced risk for RA in patients who were female, CRP-positive, RF-positive, DAS28 ≥ 3.20, or ESR ≥ 25. Compared with the controls, the average level of TLR4 protein in plasma of RA patients was increased. In addition, RA patients exhibited higher levels of TLR4 mRNA than controls (P < .05).
Conclusion: These results demonstrate the TLR4 rs7873784 G/C polymorphism to relate to a decreased risk for RA in a Chinese population.
Keywords: Toll-like receptor 4; gene polymorphism; rheumatoid arthritis.