The largest genetic study carried out in psychiatry has linked 108 genes with schizophrenia. Eighty of them were not known previously to have any association with the disease, which affects about one person in 100 but is not well controlled by existing treatments.
An international research consortium, which compared the DNA of 37,000 people with schizophrenia to that of 110,000 healthy controls, found a wide range of genetic differences between the groups. Each mutation on its own has only a small impact on an individual’s risk of becoming schizophrenic but taken together the 108 differences show that susceptibility to the disease has a strong hereditary component.
“The fact that we were able to detect genetic risk factors on this scale shows that schizophrenia can be tackled by the same approaches that have already transformed our understanding of other diseases,” says Michael O’Donovan of Cardiff University, senior author of the study, which is published in Nature. “The wealth of new findings have the potential to kick-start the development of new treatments in schizophrenia, a process which has stalled for the last 60 years.”
Although the authors have not put forward a new biological hypothesis for the cause of schizophrenia, the findings include some interesting clues. One is that abnormalities in the brain’s dopamine-signalling system are involved; all schizophrenia drugs target dopamine signalling but this is the first evidence of its involvement in the disease.