Association study of dopamine receptor D₂TaqI A polymorphism and reward-related personality traits in healthy Korean young females

Background: Genetic factors make a significant contribution to the determination of human personality traits. We aimed to investigate the possible relationship between dopamine receptor D₂ (DRD2) TaqI A polymorphism and the reward-related personality traits as measured by the Carver and White Behavioral Inhibition System/Behavioral Approach System (BIS/BAS) scales and Cloninger's Temperament and Character Inventory (TCI). Methods: The sample consisted of 267 female healthy Korean unrelated university students (age: 23.12 ± 3.22 years) and they filled out the BIS/BAS scales and the TCI. Genomic DNA was isolated from whole blood and genotyped with the fluorescence polarization detection method. The effect of the independent variables (DRD2 genotypes) on the dependent variables were analyzed by multivariate and subsequent univariate ANOVA. Results: We found significant associations between the A1 allele of the DRD2 TaqI A polymorphism and a high BAS-RR score (reward responsiveness). No significant association was observed between DRD2 polymorphisms and other factors of the BIS/BAS scales and TCI. Conclusion: These findings suggest the notion that DRD2 TaqI A polymorphism contributes to high reward sensitivity, which measures anticipation and positive response towards reward.