THURSDAY, May 4, 2006 (HealthDay News) -- By deleting a gene called PTEN in certain parts of the brain, scientists created mice that exhibited behaviors similar to those of people with autism.
Researchers at the University of Texas Southwestern Medical Center at Dallas said the results confirm recent indications that a mutation in the PTEN gene may cause at least some forms of autism. Some people with autism have mutations in this gene, but it's been unclear whether this can actually cause the disorder.
The gene was deleted from the front of the brain and from areas of the hippocampus, a structure involved in memory and other functions. The mice displayed autistic-like traits such as an oversensitivity to stimuli and deficits in social interaction. Along with altered behavior, the mice also had physical abnormalities in their brains.
"The exciting thing about this mouse is it helps us to zero in on at least one anatomic location of abnormality, because we targeted the gene to very circumscribed regions of the brain," study senior author Dr. Luis F. Parada, director of the Center for Developmental Biology, said in a prepared statement.
"In diseases where virtually nothing is known, any inroad that gets into at least the right cell or the right biochemical pathway is very important," Parada said.
The study appears in the May 4 issue of Neuron.
Compared to normal mice, the brains of the altered mice were noticeably altered in the areas where PTEN was deleted. Nerve cells were thicker than normal and had a higher-than-normal number of connections to other nerve cells, which may explain problems with sensory overload.
"It would be really exciting if it turned out that we've zeroed in on the anatomical regions where things go wrong in autistic patients, regardless of how the autism occurs," Parada said.
The next phase of this research is to treat the altered mice with drugs in order to determine whether it's possible to reverse the condition.
More information
The U.S. National Institute of Neurological Disorders and Stroke has more about autism.
