Correlation of CRP genotypes with serum CRP levels and the risk of rheumatoid arthritis in Chinese Han population

Objective C-reactive protein (CRP) is an important index for evaluating the disease activity of rheumatoid arthritis (RA). CRP may play a direct role in bone destruction in RA. Studies have demonstrated that serum CRP levels had a close correlation with tissue inflammation scores in patients with RA. In addition, genetic factors play a crucial role in the development of RA. In this study, we aimed to investigate the relationship between the CRP gene variants (rs1205 polymorphism) and the risk of RA in Chinese Han population. Methods 502 RA patients and 581 controls were included in this study. The associations between CRP gene variants and CRP levels and RA risk were investigated. Results We found that TT/ TT + CT genotype was significantly related with an increased risk of RA (TT vs CC: OR, 1.56, 95%CI, 1.01–2.40, P = 0.045; TT + CT vs CC: OR, 1.30, 95%CI, 1.02–1.65, P = 0.032). In addition, T allele was shown to associate with an elevated risk of RA. After subgroup analysis, we found that rs1205 polymorphism was significantly related with an enhanced risk of RA among females, individuals lower than 60 years, and subjects with a BMI > 25 kg/m 2 . Furthermore, data showed that the CRP gene rs1205 polymorphism correlated with CRP and ESR levels. Furthermore, the TT genotype was significantly associated with a reduction of CRP levels compared with CT or CC genotype. Conclusions To sum up, this study reveals that rs1205 polymorphism of the CRP gene is related with an increased risk of RA and CRP levels in Chinese Han population. Key Points • The CRP gene rs1205 polymorphism is related with a higher risk of RA. • The CRP gene rs1205 polymorphism correlates with CRP and ESR levels. • The TT genotype of rs1205 polymorphism is linked with a reduction of CRP levels.