Scientists in Germany have provided the first evidence that genetic risk for psychotic illnesses is linked, at least in part, to abnormal connections between different brain areas.
Andreas Meyer-Lindenberg of the University of Heidelberg and his colleagues studied 115 healthy people with or without a particular variant of the gene ZNF804A. The variant has been identified in genome-wide association studies as possibly conferring a small risk for developing schizophrenia or bipolar disorder. The authors performed brain imaging while volunteers carried out cognitive tasks relevant to these disorders.
The team found that although the risk gene does not influence the strength of activation in various brain areas, connectivity between some areas is either reduced or increased in risk-gene carriers — in a pattern reminiscent of that seen in patients.