Is there an active gene-environment correlation in adolescent drinking behavior?

A scale based on alcohol-related behaviors and an item on shared friends from the National Merit Twin Study were used in an attempt to confirm the finding of Cleveland et al. (1995, J Genet Psychol 166:153-169) of gene-environment correlation in adolescents' drinking behavior, a correlation based on the differential selection of peers. Results from samples of 490 MZ and 336 same-sex DZ pairs were consistent in direction with the hypothesis, although quantitatively modest. This consistency appeared, however, to depend entirely on the female twins in the sample.