Scientists have suggested that an individual’s risk of schizophrenia is roughly half dictated by their genetic make-up, and half by other factors during their lives. However, on both sides of this equation, much has still to be revealed about the precise causes.
The three large-scale projects have taken a step towards unraveling the genetic picture of schizophrenia.
Two separate international groups, both testing thousands of people with schizophrenia and healthy volunteers, identified the same two rare genetic variants, which appeared to contribute strongly to the chances of developing the disease.
Professor O’Donovan of Cardiff University School of Medicine said that while the research was an important step – and could eventually lead to greater understanding, or even better treatment, for schizophrenia, scientists were still far from having a complete picture of how various genetic flaws might work together or separately to produce schizophrenia symptoms. He said it was possible that further study would uncover many different genetic "routes" to schizophrenia symptoms.
Jane Harris, from the mental health charity Rethink, welcomed the advance, but urged people to focus on aspects they could change to reduce the risk of schizophrenia. According to her lots can be done – its half nature and half nurture. For example, obstetric complications, or cannabis use, have been linked with an increased risk of schizophrenia.
"Genetics is just a really gray area, and there is a danger people will think you can predict it, or even pretty much eliminate it”, she said.
Although the research is important, as it could eventually shed more light on those at greater risk. However, these findings should be treated with caution, as they may be adding to the confusion in a world where scientific studies into the genetic cause or causes of schizophrenia have to date yielded many false positives and led down unrealistic hope.