Neuroscientists Sam Wang and Sandra Aamodt have a guest post on Olivia Judson’s NY Times blog discussing the complex interplay between genes and environment in the determination of personality traits. A taste:
So some of the effects that we call “genetic” (or “nature”) are the
indirect result of people being drawn to particular environments
because of their personality. Or to put it another way, some
“environmental” (or “nurture”) effects are actually attributable to
It’s worth noting that similar effects can occur for other traits: for instance, a genetic variant that increased sugar cravings or decreased motivation to exercise could have an effect on obesity risk; a variant that increased susceptibility to a specific virus might increase the risk of auto-immune diseases triggered by viral infection. In each case, the genetic variant increases disease risk indirectly by altering exposure to an environmental risk factor.