Two extensive international studies have independently identified DNA mutations that have a big impact on the risk of schizophrenia. Using different methods, two research groups found that people missing specific "chunks" of DNA run a much higher risk of schizophrenia.
Although the DNA mutations are found in only 1% of people living with schizophrenia, the mutations increase the risk of developing schizophrenia in the first place by as much as 15-fold.
The results of the studies, headed by Dr. Pamela Sklar of Massachusetts General Hospital and Dr. Kari Stefansson of Decode Genetics in Iceland, suggest that the genetic component of schizophrenia is a large number of rare variations, rather than a few common variations.
In other words, the genetic mutations causing schizophrenia may not be consistent across the population. The disease may be driven by a constant flow of new mutations.
Dr. Sklar told the Associated Press that it is not unusual for a very rare cause of a disease to provide insights that apply more generally, even though they may not represent a breakthrough tied to a cure. They may eventually suggest "new avenues" for researching new therapies, she told Reuters news services.
In an interview with Reuters, David St. Clair of Scotland, who was involved in both studies, called the findings "the beginning of a new era in schizophrenia research."