Objective Recent research suggests that Tourette's syndrome (TS) may result from a defect in the dopamine system. The dopamine 1 receptor (DRD1) gene is a candidate gene in the study of the etiology of neuropsychiatric diseases that may involve dopaminergic abnormalities. We sought to test the hypothesis that the DRD1 gene might play a role in TS. Methods By performing an association study, we collected an independent sample of patients from the midland region of Taiwan and investigated whether DRD1 gene polymorphisms can be used as markers of susceptibility to TS. A total of 148 children with TS and 83 normal control subjects were included in the study. A polymerase chain reaction was used to identify the A/G polymorphism of the DRD1 gene. Genotypes and allelic frequencies for the DRD1 gene polymorphisms in both groups were compared. Results The results showed that genotypes and allelic frequencies for the DRD1 gene polymorphisms in both groups were not significantly different. Conclusion These data suggest that DRD1 gene may not be a useful marker for prediction of the susceptibility of TS. (C) 2004 Lippincott Williams Wilkins.
