Genetic epidemiology of psychiatric disorders.

Perhaps more than any other domain, the search for etiologic factors in psychiatry has been characterized by an enduring "nature versus nurture" debate, with researchers in medicine, psychology, and public health traditionally emphasizing separate causal factors in the generation of mental disorders. More recently, researchers have increasingly embraced a biopsychosocial model based on a growing body evidence that psychiatric disorders are determined by an interaction of multiple factors. Genetic epidemiology reflects this comprehensive approach by clarifying how both genetic and environmental components produce the complex phenotypes of various forms of disorders. However, its application to psychiatry is still relatively new and its methods and contributions within this domain are not well understood. The purpose of this presentation is to review issues and methodological concepts basic to the genetic epidemiology of psychiatric disorders, and to present examples of its application to this field.