An Association Study of the Dopamine D2 Receptor Taq1A Polymorphism and Temperament in Korean Pathological Gamblers

ABSTRACT

OBJECTIVE: It has been suggested that the dopamine D2 receptor gene (DRD2) is associated with pathological gambling (PG). We investigated the association of the DRD2 Taq1A polymorphism and the temperament in PG using Cloninger's temperament and characteristic inventory (TCI). METHODS: 104 PG patients and 114 control subjects were recruited. Tests for DRD2 Taq1A polymorphism were conducted in both PG patients and controls. PG patients were requested to complete the TCI. RESULTS: There were no significant differences in frequencies of the genotype (chi2 = 0.77, p = 0.681), allele (chi2 = 0.52, p = 0.469), and allele (A1) carrier (chi2 = 0.15, p = 0.695) between the PG patients and the control group. When we compared the TCI profile in the PG patients according to genotypes, there were significant differences in harm-avoidance (HA, p = 0.033), and self-directedness (SD, p = 0.012) among genotypes. These difference were more evident between A1 allele carriers and non-carriers (HA, p = 0.009 and SD, p = 0.004). CONCLUSION: Present results suggest Taq1A polymorphism may not play an important role in the susceptibility to pathological gambling in our population. However, Taq1A polymorphism might be associated with some temperament in Korean PG patients.