"…(G)enes and environment cannot be viewed as totally separate and independent."
"Much of the writing on environmental risk factors tends to imply that risk effects operate across the population as a whole. However, the evidence is clear-cut that this is rarely the case. In particular,… genetic influences play a major role in moderating environmental effects."
"…(V)irtually all major environmental effects involve genetic mechanisms of one sort or another. Psychosocial researchers ignore these genetic effects at their peril."
Michael Rutter, in Genes and Behavior: Nature-Nurture Interplay Explained, Blackwell Publishing, 2006