The findings from this study contribute further to the growing literature demonstrating both that exposure to certain “environmental” variables is not random, but is in part influenced by one’s own genotype, and that the “environment” may act to moderate the genetic and environmental etiology of a phenotype. Furthermore, these findings demonstrate that failing to consider either correlations or moderations of the kind described here may result in failure to fully understand the mechanisms by which the genes and the environment influence the phenotype.
