Using data from a general community twin sample, we have shown that a composite alcohol factor score is highly reliable (see also Agrawal et al. [39]), moderately heritable (50%), and has a high genetic correlation with AD symptomatology (rG=0.97), indicating that genetic influences on dependence risk and consumption overlap considerably in the general population. We previously noted a smaller genetic association with confidence intervals that excluded unity (rG=0.63, CI: 0.53–0.72 [29]). However, the previous analyses assessed consumption at the time of interview and included consumption assessments for AD individuals.
