Genetic and Environmental Influences on the Ages of Drinking and Gambling Initiation: Evidence for Distinct Etiologies and Sex Differences

Investigate the genetic and environmental contributions to age at first drink (AFD) and age first gambled (AFG), assess their overlap and examine sex differences.






Univariate twin models were fit to decompose the variation in AFD and AFG into additive genetic, shared environmental, and unique environmental factors. Bivariate genetic models were fit to assess the genetic and