[Genetic variation with increased risk of schizophrenia].

Schizophrenia is a complex genetic disorder which is caused by multiple heritable and environmental factors. Large-scale screening of the entire DNA has recently resulted in the identification of several DNA variants associated with schizophrenia. The variants identified are single nucleotide polymorphisms (SNPs) with a high frequency in the population and a small effect, and rare copy number variants (CNVs) with larger effects. Variants are not unique to patients, and appear to be involved in multiple psychiatric disorders. The underlying biological mechanisms are not evident. Together, the identified variants only explain a fraction of all cases of the disease. Genetic testing of family members of patients may become feasible in the near future. For other clinical applications additional variants need to be identified first.