To summarize current knowledge about genetic susceptibility to mood disorders and examine ethical and policy issues that will need to be addressed if robustly replicated susceptibility alleles lead to proposals to screen and intervene with persons at increased genetic risk of developing mood disorders.
Method:
Empirical studies and reviews of the genetics of unipolar and bipolar depression were collected via MEDLINE and psycINFO database searches.
Results:
A number of candidate genes for depression have been identified, each of which increases the risk of mood disorders two- or threefold. None of the associations between these alleles and mood disorders have been consistently reported to date.
Conclusions:
Screening the population for genetic susceptibility to mood disorders is unlikely to be a practically useful policy (given plausible assumptions). Until there are effective treatments for persons at increased risk, screening is arguably unethical. Screening within affected families to advise on risks of developing depression would entail screening children and adolescents, raising potentially serious ethical issues of consent and stigmatization. Genetic research on depression should continue under appropriate ethical guidelines that protect the interests of research participants.
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