DAT1 and alcohol use: differential responses to life stress during adolescence

Stressful life events can impact both substance use initiation and the quantity of substances consumed by adolescents; however, the effect of stress on substance use may be contingent on other factors including social support, peers, and genotype. DAT1, a polymorphic dopamine transporter gene, is one such factor that may be responsible for differential susceptibility to cumulative life pressures. Data from the National Longitudinal Study of Adolescent Health were utilized to determine whether adolescents with the 10-repeat allele are more likely to respond to life stresses by engaging in alcohol use than those without the allele. Respondents' self-reports of key stressors were used to create a composite life stress scale. The interaction of this measure with the number of 10-repeat DAT1 alleles was evaluated in series of logistic regression models. A significant interaction emerged between stressful life experiences and DAT1 for alcohol use among females, but this pattern was not seen in males. Females with the 10-repeat allele appear to be more sensitive to life stress as compared to those without the allele. It appears that variation in the DAT1 gene may help explain why some women are more likely to consume alcohol when confronted with stress. It, however, does not appear to condition the reaction of men, in terms of alcohol use, to stress.