multiple ways. First, its relationship with AD may be viewed in the context of unmeasured gene-measured environment correlation (or rGE) where the same latent/unmeasured genetic factors that induce individual differences in AD phenotypes also increase the likelihood of exposure to alcohol at an early age (Scarr, 1992; Scarr and McCartney, 1983). This could occur passively, through parental drinking behaviors or actively, through seeking out (like) peers who engage in problem behaviors that include early substance use.
