Study finds first-ever genetic animal model of autism

December 08, 2007

Boca Raton, FL, December 8, 2007 - By introducing a gene mutation in mice, investigators have created what they believe to be the first accurate model of autism not associated with a broader neuropsychiatric syndrome, according to research presented at the American College of Neuropsychopharmacology annual meeting. This animal model could help researchers better understand abnormal brain function in autistic humans, which could help them identify and improve treatment strategies. Broader neuropsychiatric conditions include Fragile X, the most common cause of inherited mental impairment, and Rett Syndrome, a childhood neurodevelopmental disorder characterized by normal early development followed by slowed brain and head growth, seizures, and mental retardation.

Autism is a neuropsychiatric disorder characterized by repetitive behaviors and by impairment in social interactions and communication skills. These symptoms can coexist with either enhanced or decreased cognitive abilities and skills.

"Prior to this study we knew next to nothing about the mechanisms of autism in the brain," says study researcher Craig M. Powell, M.D., Ph.D., assistant professor of neurology and psychiatry at the University of Texas Southwestern Medical Center at Dallas. "With this research, we can study changes in the brain that lead to autistic behaviors and symptoms, which may help us understand more about progression and treatment of the disorder."

The research team, led by Thomas Südhof, M.D., professor and chairman of neuroscience at UT Southwestern, replaced the normal mouse neurologin-3 gene with a mutated neuroligin-3 gene associated with autism in humans. By doing so, the team was able to create a gene in the mice that is similar to the human autism disease gene. While the result amounted to a very small change in their genetic makeup, it perfectly mimicked the same small change occurring in some patients with human autism.

Dr. Powell studied the genetically altered mice and found that, when examined in behavioral tests that may reflect key signs of autism, they showed decreased social interaction with other mice; other traits, such as anxiety, coordination and pain sensitivity, were unaffected. These social interaction deficits, Dr. Powell says, are hallmark features of human autism. In addition, the mice showed enhanced spatial learning abilities, which may resemble the enhanced cognitive abilities in autistic savants (people who have a severe developmental or mental handicap as well as extraordinary mental abilities).

"These findings could be especially helpful in identifying novel treatment approaches. We already know that inhibitory chemical synaptic transmission from one neuron to the next is increased in this mouse model. Now we can test drugs that decrease this effect directly in the mice and ask whether this reverses their social interaction deficits," Dr. Powell says. "For now, the mainstay of autism treatment is still behavioral therapy. The earlier we can get patients involved with behavioral interventions, the better off people with autism will be." Dr. Powell adds that the model gives researchers insight into mouse brains which share important parallels with brains of living humans, which can only be studied in limited ways with the use of new brain imaging tools.
-end-
ACNP, founded in 1961, is a professional organization of more than 700 leading scientists, including four Nobel Laureates. The mission of ACNP is to further research and education in neuropsychopharmacology and related fields in the following ways: promoting the interaction of a broad range of scientific disciplines of brain and behavior in order to advance the understanding of prevention and treatment of disease of the nervous system including psychiatric, neurological, behavioral and addictive disorders; encouraging scientists to enter research careers in fields related to these disorders and their treatment; and ensuring the dissemination of relevant scientific advances.

American College of Neuropsychopharmacology

Related Autism Articles from Brightsurf:

Autism-cholesterol link
Study identifies genetic link between cholesterol alterations and autism.

National Autism Indicators Report: the connection between autism and financial hardship
A.J. Drexel Autism Institute released the 2020 National Autism Indicators Report highlighting the financial challenges facing households of children with autism spectrum disorder (ASD), including higher levels of poverty, material hardship and medical expenses.

Autism risk estimated at 3 to 5% for children whose parents have a sibling with autism
Roughly 3 to 5% of children with an aunt or uncle with autism spectrum disorder (ASD) can also be expected to have ASD, compared to about 1.5% of children in the general population, according to a study funded by the National Institutes of Health.

Adulthood with autism
The independence that comes with growing up can be scary for any teenager, but for young adults with autism spectrum disorder and their caregivers, the transition from adolescence to adulthood can seem particularly daunting.

Brain protein mutation from child with autism causes autism-like behavioral change in mice
A de novo gene mutation that encodes a brain protein in a child with autism has been placed into the brains of mice.

Autism and theory of mind
Theory of mind, or the ability to represent other people's minds as distinct from one's own, can be difficult for people with autism.

Potential biomarker for autism
A study of young children with autism spectrum disorder published in JNeurosci reveals altered brain waves compared to typically developing children during a motor control task.

Autism often associated with multiple new mutations
Most autism cases are in families with no previous history of the disorder.

State laws requiring autism coverage by private insurers led to increases in autism care
A new study led by researchers at the Johns Hopkins Bloomberg School of Public Health has found that the enactment of state laws mandating coverage of autism spectrum disorder (ASD) was followed by sizable increases in insurer-covered ASD care and associated spending.

Autism's gender patterns
Having one child with autism is a well-known risk factor for having another one with the same disorder, but whether and how a sibling's gender influences this risk has remained largely unknown.

Read More: Autism News and Autism Current Events
Brightsurf.com is a participant in the Amazon Services LLC Associates Program, an affiliate advertising program designed to provide a means for sites to earn advertising fees by advertising and linking to Amazon.com.