Pathophysiology of Patients with Schizophrenia: Genetic and Environmental Factors

Abstract

Schizophrenia is a debilitating disorder with a prevalence of approximately 0.5%-1% within any given population. The pathophysiology of schizophrenia involves complex genetic, environmental, and psychological etiologies. Here we summarize 26 years of research completed by the Juntendo University Schizophrenia Projects study group on the “biopsychosocial model” of schizophrenia. Clinical brain morphological abnormalities in schizophrenia were detected with magnetic resonance imaging, and these findings led to gene expression analyses of neurotransmitters. The familial aggregation pattern in schizophrenia led to the completion of genetic studies, including linkage and genome-wide analyses, and studies on environmental factors, such as nutrition, aging, stress, and inflammation. Furthermore, we developed a collaborative multicenter study that consisted of a large number of samples. This study enabled us to clearly identify the relevant pathophysiology of schizophrenia, including genetics, altered neurotransmission, brain morphology, and clinical features.