Schizophrenia Yields Some Genetic Secrets
Wednesday, July 30, 2008; 12:00 AM
WEDNESDAY, July 30 (HealthDay News) -- Moving closer to the causes and effective treatment of schizophrenia, researchers say they've found specific gene variations linked to the condition.
Specifically, three rare deletions in the human genome appear to raise the risk of developing the devastating brain disease considerably.
"These findings give a great deal of hope -- for individuals with schizophrenia and their families and loved ones and caregivers -- that we're moving towards an understanding of the causes of the disease," said Dr. Pamela Sklar, corresponding author of a paper appearing inNatureand director of genetics at Harvard Medical School, Boston.
Additional findings, all reported at a Tuesday press teleconference, are detailed in two other papers published in the July 30 online editions ofNatureandNature Genetics.
But the current findings are just the tip of the iceberg, the researchers stressed.
"We've only explained a tiny fraction of why people might develop schizophrenia, and much more work needs to be done to connect specific changes to the full spectrum of other types of genetic factors that might influence schizophrenia, as well as ways they might interact with the environment," added Sklar, who is a member of the International Schizophrenia Consortium, which conducted one of the studies.
Schizophrenia, a devastating disorder characterized by hallucinations and delusions, affects some 1 percent of the population, usually appears in late adolescence or early adulthood and, despite some effective treatments, tends to be chronic.
Breakthroughs in understanding this disorder have been few and far between.
"We've been working on schizophrenia for rather more years than we care to think, and successes have not been dramatic," acknowledged Michael O'Donovan, lead author of theNature Geneticsstudy and professor of psychiatric genetics at Cardiff University in the United Kingdom.
"There has been precious little on diseases of the brain, and what seems to be emerging is that a lot of risk of brain diseases, including schizophrenia and autism, seems to be conferred by rare [gene] variants like rare deletions," said Dr. Kari Stefansson, senior author of one of theNaturepapers and CEO of deCODE in Reykjavik, Iceland.
Schizophrenia tends to run in families, hence the focus on genetic determinants of the disease.
The first two papers, inNature, compared the genomes of 3,300 individuals with schizophrenia against those of 3,200 individuals without the illness.