Schizophrenia is a complex disorder. The cause of schizophrenia lies in a complex interaction between genes and environment. Genetic variation could lead to altered brain structure and/or function. These changes could predispose a person to developing schizophrenia in the face of environmental stressors. MRI of the brain provides a way to detect changes in brain structure due to genetic effects and those due to disease progression.
Patients with schizophrenia have reduced grey matter volume and altered white matter connections. Some of these changes could have a genetic basis. Voxel based morphometry provides an unbiased whole brain approach to explore effects of genetic polymorphisms on grey matter and white matter volumes in schizophrenia.
Formation of gyri and sulci begin at the age of 16 weeks in utero in humans. Genetic variation may affect rates of grey matter and white matter development thus affecting formation of gyri. As some genes implicated in schizophrenia affect the development of the brain, these may result in abnormal gyrification. Measuring cortical gyrification in healthy twins and twins discordant for schizophrenia (i.e., one twin has schizophrenia while the cotwin is healthy) can help us differentiate between genetic effects and disease effects on cortical gyrification in schizophrenia.