Association between NOS3 genetic variants and coronary artery disease in the Han population

The enzyme endothelial nitric oxide synthase (NOS3) is an important mediator of atherosclerotic disease and is associated with coronary artery disease (CAD). There is growing evidence that polymorphisms in NOS3 influence the progression of CAD; however, there is also a controversy regarding the association of polymorphisms in the gene encoding NOS3 and CAD. To determine if the NOS3 genetic variants are associated with CAD in the Han Chinese, we examined the potential association between CAD and eight single nucleotide polymorphisms (rs1799983, rs2070744, rs11771443, rs3918188, rs2853796, rs7830, rs1541861, and rs2853792) of the NOS3 using the MassARRAY system. The allelic and genotypic frequencies of the rs1799983 (promoter regions) and rs2070744 (intron 1) polymorphisms in patients with CAD were significantly different from those in healthy controls. These patients had significantly higher frequencies of the rs1799983 T allele (chi(2) = 7.717, P = 0.007, OR = 1.649, 95% CI = 1.41-2.382) and the rs2070744 G allele (chi(2) = 4.548, P = 0.033, OR = 1.490, 95% CI = 1.031-2.153). Strong linkage disequilibrium was observed in three blocks (D' > 0.9). In block 1, significantly more T-T-C haplotypes (chi(2) = 5.537, P = 0.019, OR = 0.632, 95% CI = 0.430-0.927) were found in controls. These findings point to a role for NOS3 polymorphisms in CAD in the Chinese Han population, and may be useful for future investigations on the pathogenesis of CAD.