Genetic moderation of environmental risk for depression and anxiety in adolescent girls

Department of Human Genetics, Virginia Institute for Psychiatric and Behavioral Genetics, Virginia Commonwealth University, Richmond, Virginia 23298-0030, USA.
The British Journal of Psychiatry (Impact Factor: 7.34). 09/2001; 179:116-21. DOI: 10.1192/bjp.179.2.116
Source: PubMed

ABSTRACT There is huge individual variation in people's response to negative life events.
To test the hypothesis that genetic factors moderate susceptibility to the environmentally mediated risks associated with negative life events.
The Virginia Twin Study of Adolescent Behavioral Development (VTSABD) was used to study the effects of independent life events (assessed from maternal interview) on depression/anxiety (assessed from child interview) in 184 same-gender female twin pairs, aged 14--7 years, measured on two occasions.
There was no genetic effect on the independent negative life events studied. A significant gene-environment interaction was found using structural equation modelling. There was no effect of independent life events on adolescents' depression in the absence of parental emotional disorder, but a significant effect in its presence.
There is an environmentally mediated effect of life events on depression/anxiety. Genetic factors play a significant role in individual differences in susceptibility to these environmentally mediated risks.

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