P3 event-related potential, dopamine D2 receptor A1 allele, and sensation-seeking in adult children of alcoholics

Background: Research has indicated a close relationship between the P3 event-related potential and the dopamine D2 receptor Al allele in individuals at high risk for alcoholism. Other research has suggested an association between the dopamine D2 receptor A1 allele and sensation-seeking. In this study, we further examined the relationships between the P3, the A1 allele, and sensation-seeking in a sample of nonalcoholic adult children of alcoholics. Methods: Participants (n = 57; range, 19-30 years; 41 women), who performed a visual novelty oddball task to elicit the P3, were asked to fill in personality questionnaires, including Zuckerman's Sensation-Seeking Scale, and were classified according to the presence of the dopamine D2 receptor A1 allele. The effects of sex, age, and socioeconomic status were assessed to determine whether these variables affected the relations between the P3, the A1 allele, and sensation-seeking. Results: A small P3 amplitude was associated with high sensation-seeking, particularly with high disinhibition. The presence of the A1 allele was also associated with high disinhibition, but only in men. By contrast, P3 amplitudes and latencies were not associated with the presence of the A1 allele. Conclusions: Although a small P3 amplitude, high sensation-seeking, and the presence of the A1 allele were all associated with alcoholism risk, these findings indicate that these three characteristics together do not reflect a common risk factor in alcoholism.