RESUMO
<p><b>OBJECTIVE</b>Recent studies have found that the variation of G894T on the region of T786C and 7th exon promoted by endothelial nitric oxide synthase (eNOS) gene is associated with cardiovascular disease. This research explored possible correlations between eNOS gene polymorphisms and orthostatic intolerance (OI) in children through linkage disequilibrium analysis between eNOS genes T786C and G894T and OI.</p><p><b>METHODS</b>PCR, Macrorestriction Map and other molecular biotechnology were used to determine the genotypes of eNOS/T786C and G894T in 60 OI probands and their parents. Correlation analysis and transmission disequilibrium test (TDT) between T786C, G894T and OI were performed.</p><p><b>RESULTS</b>There was linkage disequilibrium of eNOS/T786C and G894T gene polymorphisms in the occurrence of childhood OI (P<0.05).</p><p><b>CONCLUSIONS</b>eNOS genes T786C and G894T may be associated with the pathogenesis of OI.</p>