Objective: To determine whether endothelial nitric oxide synthase (eNOS) polymorphisms confer susceptibility to systemic lupus erythematosus (SLE).
Methods: A meta-analysis was conducted on the associations between the 4b/a, G894T, and C786T polymorphisms of eNOS and SLE and lupus nephritis (LN) (when available) using (1) the allele contrast, (2) the recessive, (3) the dominant, and (4) the additive models.
Results: A total of eight studies, which included 1,297 cases and 1,214 controls, were included in the meta-analysis. Meta-analysis showed no association between SLE and the 4b/a polymorphism in any study subjects. Stratification by presence of LN indicated a significant association between the a allele and the aa + ab genotype of the 4b/a polymorphism and LN in SLE patients [odds ratio (OR) = 2.125, 95% confidence interval (CI) = 1.289-3.054, p = 0.003; OR = 2.655, 95% CI = 1.509-4.671, p = 0.001]. No association was found between SLE and the G894T polymorphism using the allelic, recessive, or dominant, or additive models. Meta-analysis of the T786C polymorphism showed a tendency to an association between the TT genotype and SLE (OR = 1.220, 95% CI = 1.000-1.489, p = 0.050), and meta-analysis of the TT versus CC genotype of the C786T polymorphism in group in Hardy-Weinberg equilibrium revealed a significant association between the TT genotype and SLE (OR = 1.643, 95% CI = 1.021-2.644, p = 0.041).
Conclusions: This meta-analysis of published studies shows that the 4b/a polymorphism may be associated with the development of LN, and the C786T polymorphism may be associated with SLE susceptibility.