In the main effects for the time-to-first-marriage and divorce models, we included AUD, the alcohol problems PRS, and psychiatric comorbidities as predictors. A random intercept for subject with correlation structure defined by a genetic relatedness matrix (GRM) was used to estimate for the additive genetic variance contributing to marriage/divorce. An additional random intercept for family grouping with independence correlation structure was used to account for familial environment variance contributing to marriage/divorce. Age was mean centered. The alcohol problems PRS and 10 PCs were standardized to have a mean of 0 and standard deviation of 1.
