Genetic mediation of the relationship between social support and psychological well-being.

This study assessed genetic and environmental influences on the association between social support and psychological functioning using the combined adoption/twin design from the Swedish Adoption/Twin Study of Aging. A subsample of 424 twin pairs, 50 years and older, was used: 64 pairs of identical twins reared apart, 95 pairs of identical twins reared together, 132 pairs of fraternal twins reared apart, and 133 pairs of fraternal twins reared together. Multivariate model-fitting analyses indicated that the relationship between the perceived adequacy of social support and psychological well-being (depression and life satisfaction) was mediated in part by genetic factors.