Nature and Nurture in Personality

An interaction between individual and contextual factors is the central theme in development of personality. Molecular genetics offers the most valuable opportunity for increasing our understanding of the joint effect of nature and nurture. Sensitivity to environmental adversities and benefits may be conditional on genetic background, and the nature-nurture interactions may be of greater importance than direct gene-trait associations. In our recent series of studies, we have shown that different variants of serotonergic and dopaminergic genes may moderate the influence of environmental conditions on a range of psychological outcomes, at least on temperament, depression, and hostility. These studies suggest that, depending on their genotype, people may be differentially sensitive to the environmental conditions they encounter. In light of these results, it seems highly plausible that the effects of genes may become evident only when studied in the context of environmental factors.