A Genetic Risk Adoption Design for Psychiatric and Substance Use Disorders

Using a more incisive measure of genetic effects, the novel adoption design used in this cohort study provides findings broadly similar to traditional adoption models. Rearing effects were strongest for substance use disorders, modest for internalizing disorders, and absent for severe disorders. Indirect genetic effects in the father on offspring risk were clearly observed and were not diagnostically specific. In rearing-only paternal-offspring relationships, elevated paternal genetic risk for internalizing and substance use disorders increased offspring risk for MD and AUD.