A public health genetic approach for schizophrenia

Schizophrenia is a complex disease resulting from the interplay of genetic and environmental factors. However, psychiatric genetics and epidemiology have often worked as independent research fields.

To review the evidence about the gene-environment interplay involved in the development of schizophrenia.

Systematic review of medical and psychological databases.

On one hand, quantitative and molecular genetics showed high heritability for schizophrenia and identified genes likely to be involved in its pathophysiology. The strength of the association between candidate genes and schizophrenia is however modest, and the need for a more appropriate conceptualization of the genetic risk has been claimed. On the other hand, psychiatric epidemiology described several environmental factors liked with the onset or the course of schizophrenia. The observational nature of epidemiology, however, may hamper inference on causation. Gene-environment correlations and interactions influence the exposure and the vulnerability to the environment, respectively. Current findings suggest that gene-environment correlations and interactions may be common phenomena in the pathophysiology of schizophrenia. The consideration of gene-environment interplay may help to overcome many limitations of genetic and epidemiological studies in psychiatry and suggest innovative preventive and therapeutic strategies.

Taking into account the complexity of schizophrenia pathophysiology, mental health genetics may provide a comprehensive and heuristic model of disease.