| Popis: |
Background: Molecular genetic studies of alcohol and nicotine use have identified many genome-wide significant loci. We examined associations between drinking and smoking polygenic scores (PGS) and trajectories of alcohol and nicotine use outcomes from late childhood to early adulthood, substance-specific versus broader-liability PGS effects, and if PGS performance varied for consumption and problematic use. Methods: We fit latent growth curve models with structured residuals to scores on measures of alcohol and nicotine use and problems from age 14 to age 34. We then estimated associations between the intercept (initial status) and slope (rate of change) parameters and PGSs for drinks per week (DPW), problematic alcohol use (PAU), cigarettes per day (CPD), and ever being a regular smoker (SMK). PGSs were calculated for participants of the Minnesota Twin Family Study (N=3225) using results from the largest genome-wide association studies of alcohol and nicotine consumption and problematic use to date. Results: Each PGS was associated with trajectories of use for their respective substances (i.e, DPW and PAU for alcohol; CPD and SMK for nicotine). The PAU and SMK PGSs also exhibited cross-substance associations (i.e., PAU for nicotine, SMK for alcohol). The SMK PGS was a significant predictor of all nicotine and alcohol use trajectories, even after adjusting for the respective effects of all other PGSs. Conclusions: Substance use-related PGSs vary in the strength and generality versus specificity of their associations with substance use over time. The SMK PGS was the most robust predictor of substance use trajectories and seems to measure both nicotine-specific and non-specific genetic liability for substance use, and potentially externalizing problems in general. |
