Interaction between dopamine D2 receptor genotype and parental rule-setting in adolescent alcohol use: evidence for a gene-parenting interaction.

Association studies investigating the link between the dopamine D2 receptor gene (DRD2) and alcohol (mis)use have shown inconsistent results. This may be due to lack of attention for environmental factors. High levels of parental rule-setting are associated with lower levels of adolescent alcohol use and delay of initiation of drinking. We tested whether DRD2 TaqI A (rs1800497) genotype interacts with alcohol-specific parenting practices in predicting the uptake of regular adolescent alcohol use. Non-regular drinkers were selected from a Dutch, nationwide sample of 428 adolescents (mean age 13.4 years at baseline) and participated in a prospective, community-based study with three annual waves. Parental rule-setting was directly and inversely related to adolescent alcohol use over time. For DRD2 genotype no significant main effect was found. DRD2 genotype interacted with parental rule-setting on adolescent alcohol use over time: adolescents, with parents highly permissive toward alcohol consumption and carrying a genotype with the DRD2 A1 (rs1800497T) allele, used significantly more alcohol over time than adolescents without these characteristics. The DRD2 genotype may pose an increased risk for alcohol use and abuse, depending on the presence of environmental risk factors, such as alcohol-specific parenting.