Association of Serotonin Transporter Gene Polymorphism with Recurrent Aphthous Stomatitis

Background: Recurrent Aphthous Stomatitis (RAS) is one of the most common diseases of the oral cavity all over the world (5-66%). RAS has a multifactorial etiology, while psychological factors such as stress and anger play a role in its manifestation. The serotonergic mechanisms particularly the serotonin-transporter gene (5-HTT) may affect the risk of psychological alterations and stress response. The aim of the present study was to evaluate the polymorphism of the promoter region of 5-HTT (5- HTTLPR) in the patients with RAS, compared to that in the control subjects. Methods: In this case-control study, 100 patients with RAS and 100 healthy subjects were enrolled. PCR was performed on DNA of the samples, using a pair of primers capable of distinguishing S/L alleles and replicating 5-HTTLPR. Results: No statistically significant difference existed between LL and LS genotype frequencies in the case and control groups. However, SS genotype frequency was significantly higher in the case group, as compared to the control group (p=0.001). Conclusion: The conclusion of the present study demonstrated that S allele could approximately double the risk of RAS.