Re-Conceptualizing Genetic Influence in GxE Studies: Does Inherited Sensitivity to Environmental Influence Moderate the Indirect Effect of Parent Knowledge on Future Drinking?

Excessive drinking in adolescence is a public health issue with major consequences on both an individual and societal level. Elucidating genetic and environmental influences could be particularly informative for prevention efforts. One potential source of genetic influence is sensitivity to environmental influences. It was hypothesized that parent knowledge would interact with genetic sensitivity to the environment to indirectly reduce risk for alcohol problems through less adolescent rule breaking behavior. Participants (N=316) provided genetic data and reported their rule breaking behavior and past year frequency of heavy drinking, and participants’ custodial parents reported their perceived knowledge of their child’s activities. A novel index of genetic sensitivity to environmental influence was created using published methylation quantitative trait locus data from the frontal lobe. Study hypotheses were mostly not supported. The study results likely reflect the poor distribution of study variables and the limitations of the current study’s sensitivity gene score. The current study underscored the importance of adhering to methodological rigor and explored alternate conceptualizations and methods that future research could use to elucidate the role of inherited to sensitivity to environmental influences in adolescent drinking.