RESUMEN
BACKGROUND: Several genetic polymorphisms in the endothelial nitric oxide synthase (eNOS) gene are associated with the pathogenesis of rheumatoid arthritis (RA). The objective of the present study was to investigate whether the two SNPs (T-786C and G894T) of the eNOS gene are associated with rheumatoid arthritis risk in a northern Chinese population. METHODS: In this study, the eNOS genes T-786C and G894T were studied in 196 cases with rheumatoid arthritis and 201 healthy controls with gender, age and ethnicity matched. The two SNPs were genotyped using polymerase chain reaction-restriction fragment length polymorphism (PCR-RFLP). The analyses of association were statistically compared using the chi-square test with SPSS software for Windows. RESULTS: The frequency of the -786C allele was significantly higher in the rheumatoid arthritis patients than in the healthy controls (19.64% vs. 14.18%, P < 0.05). However, the 894T allele of the eNOS gene was not increased in the rheumatoid arthritis patients compared to the healthy controls. CONCLUSIONS: Individuals with the -786CC genotype have an increased risk of rheumatoid arthritis. Further study with an increased sample size is necessary for the study of the role of this SNP in rheumatoid arthritis.