Rare genetic variations tied to schizophrenia risk
NEW YORK - A new study has found that rare and previously undetectable genetic variations may significantly increase the risk that a person will develop schizophrenia.
Specialists said the study, while not identifying the cause of the disorder, provided a striking demonstration of how new gene-scanning technology can open a new frontier in the quest to understand the biology of mental disorders.
Until now, researchers had focused on finding common and known genetic variations that, when acting in some combination, might increase the risk for schizophrenia. They have had little success.
The new analysis, being published today in the journal Science, detected extremely rare and unknown mutations that turned up three to four times as often in people with schizophrenia as in those without it.
The findings point scientists to previously unappreciated developmental problems that may help them develop more effective treatments, specialists said.
Researchers have tried for generations to understand the biological underpinnings of schizophrenia, which affects 1 percent of the population, causing scrambled thinking and delusions.
The new study suggests that the genetics of the disorder are even more complex than many had presumed.
Mary-Claire King, a coauthor and a professor of medicine and genomic sciences at the University of Washington, said the findings helped explain several facts about schizophrenia, including why genetic selection has not caused it to disappear.
"A constant influx of new mutations that occur purely by chance, out of the blue, can explain the persistence of schizophrenia in all parts of the world and throughout human history," King said.
