Shared-environment etiology

The best view we have from twin studies is that schizophrenia results from both genetic and shared-environment etiological influences, with shared environment meaning classical postnatal environmental factors plus prenatal environmental factors, such as exposure to infectious agents, macro- or micronutrient dietary characteristics, and exposure to environmental toxins, teratogens, and other assaults to the prenatal environment.22 Which factors and assaults are important can differ from one individual to another for reasons still unknown. Schizophrenia is not a simple puzzle. 

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