The goal of this analysis was to describe latent genetic influences on alcohol consumption from early adolescence into adulthood in terms of the number of relevant factors and their relative influence over time. We found that two distinct latent genetic factors account for genetic variance from the ages of 12–14 years through to the ages of 30–33 years. The influence of one of these factors is largely limited to mid-adolescence and early adulthood, declining in significance beyond epoch 3 (ages 18–21 years). Thereafter, the influence of the other latent genetic factor is more pronounced. The total heritability of alcohol consumption – combining that contributed by both latent genetic factors – increases from h2 of about 0 at ages 12–14 years to h2 of about 0.40 from the age of 18–21 years to the age of 30–33 years. These estimates are consistent with those reported previously (Kendler et al. 2008b). Shared environmental influences decline over time, from 24% of the variance to 4%. Likewise, unique environmental influences account for more of the total variance at the age of 12–14 years (76%) than at the age of 30–33 years (55%).
