The present study addresses limitations of prior studies to examine whether offspring genetic predispositions for alcohol problems, as characterized by the polygenic scoring approach, moderate the effects of parental divorce and parental relationship discord on offspring alcohol outcomes in a high-risk, ancestrally diverse Collaborative Study on the Genetics of Alcoholism (COGA) sample. Genome-wide polygenic scores (PRS) represent an individual’s overall genetic liability for a given behavior/trait. This approach involves summing the number of alleles for each common genetic variants (single-nucleotide polymorphisms; SNPs), weighted by the effect size drawn from the results from genome-wide association study (GWAS) in a large-scale discovery sample (Bogdan et al., 2018). We tested two preregistered hypotheses (osf.io/nambu): Parental divorce, parental relationship discord, and higher offspring alcohol problems polygenic scores will be associated with (a) earlier age at first regular drinking and (b) higher risk of developing an alcohol use disorder.The associations of parental divorce and parental relationship discord with (a) earlier age at first regular drinking and (b) higher risk of developing an alcohol use disorder (AUD) will be stronger among offspring with higher alcohol problems polygenic scores.
