FRIDAY, Nov. 5, 2010 (HealthDay News) -- An international consortium of researchers has linked a regional abnormality found in a specific chromosome to a significantly increased risk for both autism spectrum disorders (ASD) and schizophrenia.
Although previous work has indicated that genetic mutations play an important role in the risk of both disorders, this latest finding is the first to hone in on this specific abnormality, which takes the form of a wholesale absence of a certain sequence of genetic material.
Individuals missing the chromosome 17 sequence are about 14 times more likely to develop autism and schizophrenia, the research team estimated.
"We have uncovered a [genetic] variation that confers a very high risk for ASD, schizophrenia and neurodevelopmental disorders," study author Dr. Daniel Moreno-De-Luca, a postdoctoral fellow in the department of human genetics at Emory University in Atlanta, said in a university news release.
Moreno-De-Luca further explained the significance of the finding by noting that this particular region, comprised of 15 genes, "is among the 10 most frequent pathogenic recurrent genomic deletions identified in children with unexplained neurodevelopment impairments. We believe it also may increase risk for other psychiatric conditions such as bipolar disorder."
He and his colleagues report their findings in the Nov. 4 online edition of the American Journal of Human Genetics.
Identification of this new genetic marker for autism and schizophrenia stemmed from work with about 23,000 patients diagnosed with autism, developmental delay, intellectual disability or schizophrenia, 24 of whom had the chromosome 17 deletion.
By contrast, among a pool of nearly 52,500 healthy patients, none were found to be missing the genetic material, the investigators reported.
The authors noted that prior research had established that a mutation in one of the 15 missing genes in the newly identified sequence is a cause of both renal cysts and diabetes syndrome.
More information
For more on autism, visit the U.S. National Institutes of Health.
