Chunk #34 — Examples of Specific Environments that Could be Modeled Across Species: Early Alcohol Exposures and the Peer Environment — The Peer Social Environment
The peer use environment illustrates some of the dilemmas surrounding the consideration of environmental risk factors since a substantial amount of this ostensible “environmental risk factor,” perhaps as much as 50% by adulthood, is attributable to additive genetic effects (Kendler et al., 2007). The apparent, genetically influenced “niche seeking” should not be interpreted to mean that the environment does not play an important causal role in the outcome of alcohol-related pathology. It does suggest, however, that it is not just naïve but probably incorrect to view the peer environment as an independent, environmental risk factor. Moreover, even in the context of strong selection into high drinking social environments (e.g., college fraternities and sororities), there remains nontrivial socialization effects that appear to reinforce the selection or even lead to onset or escalation in lighter drinkers (Park et al., 2009). Twin studies have suggested that the correlation between peers’ substance use and an adolescent’s own substance use reflects both genetic (selection) and environmental (socialization) processes (Dick et al., 2007a).
