Endothelial nitric oxide synthase gene polymorphisms are not associated with recurrent aphthous stomatitis

ObjectiveRecurrent aphthous stomatitis (RAS) is a common ulcerative disease of the oral mucosa. Recurrent oral aphthous ulceration is the most common and consistent feature of the more serious and systemic Behçet's disease (BD). Association of endothelial nitric oxide synthase (eNOS) gene polymorphisms with BD have been reported in different populations. This study aims to investigate if there is an association between these polymorphisms and RAS.MethodsA case–control association study using 91 Caucasoid RAS patients and 91 ethnically matched systemically healthy controls were genotyped for the −786 and 894 eNOS single nucleotide polymorphisms (SNPs) and a variable number of tandem repeat (VNTR) polymorphism. Chi-square analysis was used to compare the allele and genotype frequencies.ResultsNo significant difference was found in the distribution of allele and genotype frequencies of the −786 and +894 polymorphisms or the VNTR polymorphism between cases and controls.ConclusioneNOS gene polymorphisms associated with BD are not associated with RAS. This suggests that the oral ulceration common to both conditions may have a different underlying genetic aetiology. Although our data suggests that RAS does not have an association with eNOS, it is still possible that nitric oxide is involved in the disease process. This could still occur through localised and inflammation driven regulation by iNOS.