Association between Social Phobia and Serotonin Transporter Gene Polymorphism: Preliminary Study

Abstract

Objectives : Disturbances of serotonergic system might be related to the possible mechanism of social phobia. This study was to investigate the association of serotonin transporter gene and social phobia.Methods : Sixty nine patients with social phobia(51 male (73.9%), mean age 35.17±11.89 years) and seventy four normal controls (54 male (73.0%), mean age 33.46±9.63 years) were tested for serotonin transporter gene-linked polymorphic region(5-HTTLPR) polymorphism. Additionally, patients were grouped into 46 generalized(GEN) and 23 nongeneralized(NGEN) subgroups and 5-HTTLPR polymorphism was compared with that of normal controls. The genotypes and allele frequencies of the 5-HTTLPR polymorphism between social phobia and the control group were compared. Genomic DNA was extracted from their blood and 5-HTTLPR polymorphisms were determined by using polymerase chain reaction. Results : Significant association was observed between the S(ss) genotype and social phobia, by functional classification(p=.010). In allele frequency analysis, a significant association was also observed between the short allele and social phobia(p=.030). A significant associations between S genotype and each subgroup were observed(GEN p=.045 ; NGEN p=.033), but there were no differences in allele frequency. And, no differences in genotype and allele distribution between two subgroups were found.Conclusion : The results in our Korean sample suggest that S genotype of 5-HTTLPR may be associated with social phobia and s allele may be an important genetic factor that activates social phobic symptoms. But, further studies including large number of samples are necessary to elucidate these present findings.