Genetically Altered Mice May Provide Animal Model for Autism
A team of researchers at the University of Texas’ Southwestern Medical Center has genetically engineered mice with a genetic mutation that has been found in some people with autism. These mice may offer researchers a new means for studying how specific defects in brain development might lead to autism.
“This is the first time a mutation found in patients with autism that is not part of a known genetic syndrome has been re-created in a mouse,” explained Sophia Colamarino, Ph.D., vice president of research for Autism Speaks.
“These mice will become a very important tool for autism researchers. Ultimately they may even provide us with a model system for testing treatment approaches.”
Thomas Südhof and his colleagues at the University of Texas Southwestern Medical Center published their findings September 6, 2007, in Science Express, which provides electronic publication of selected important Science papers ahead of print.
The mice have a mutation in the gene for a protein called neuroligin-3, which operates as a cell adhesion molecule in synapses. This gene has previously been found to be mutated in a few individuals with autism. Dr. Colamarino emphasized that “although the number of autism cases caused by mutations in the Neuroligin-3 gene may not be many, studying the function of the mutated neuroligin-3 protein is essential to understanding the underlying biological mechanisms that actually create autism.”
The research was supported in part by a grant from Autism Speaks.
Read the press release from the Southwestern Medical Center below.
‘Rain Man’ mice provide model for autism
DALLAS — Sept. 7, 2007 — Mice containing a mutated human gene implicated in autism exhibit the poor social skills but increased intelligence akin to the title character’s traits in the movie “Rain Man,” researchers at UT Southwestern Medical Center have found.
The researchers’ study also shows how the mutation affects nerve function and provides an animal model that might allow further study of the debilitating condition.
“It’s an attempt to replicate, as best we can, a complicated disease that has as a symptom an inability to use language effectively,” said Dr. Thomas Südhof, chairman of neuroscience and senior author of the study, which appears online in Science Express and will be published later in Science.
Dr. Thomas Südhof “Any model we make will only be an approximation of the human condition,” he cautioned.
Autism spectrum disorders cover a wide span of conditions and symptoms, from severe mental retardation to mild social impairment. In general, people with autism have problems with social interactions, such as maintaining eye contact or reading body language. They may also exhibit stereotypical behavior, such as being obsessed with lining up objects. In the movie “Rain Man,” the title character was unable to form social bonds and became distressed when his normal routine was disrupted, yet he could perform exceptional mental mathematics.
About 1.5 million people in the United States have autism spectrum disorders, with boys affected more often than girls.
Some cases of autism are genetically linked and have been associated with mutations that affect molecules called neuroligins, which link nerve cells together.
In the latest study, the researchers introduced a mutated human form of the neuroligin-3 molecule into mice. They then tested the animals’ social interactions by exposing them to an unknown mouse in a cage. The genetically engineered mice spent less time near the strange mouse than their normal littermates and preferred to spend time with inanimate objects.
The engineered mice were significantly better than normal, though, at learning a water maze, in which they had to find and learn the location of an underwater platform. They were also better at relearning a new position of the platform after it was moved.
“When you manipulate a brain, you usually don’t improve it,” Dr. Südhof said. “The fact that we get an improvement is very good. It shows we’re changing something specific; we’re affecting how the brain processes information.”
Other tests of coordination, anxiety and motor ability showed normal results, indicating that the changes in brain activity were specific, Dr. Südhof said.
The researchers also studied the patterns of electrical activity in the brain. Normally, some nerve cells halt, or inhibit, other nerve cells from firing, while others excite action in their neighbors. An imbalance in the normal pattern is thought to be involved in autism.
Nerve cells from the genetically engineered mice showed a significantly greater inhibitory action than their normal littermates, even though only about 10 percent of the normal amount of neuroligin-3 was present. This finding was a surprise, as other studies have indicated that a loss of inhibitory action might be involved in autism spectrum disorders, the researchers said.
The results indicate that focusing on inhibitory action might be a way to treat autistic behaviors, said Dr. Südhof, director of the Gill Center for Research on Brain Cell Communication and the C. Vincent Prothro Center for Research in Basic Neuroscience. He is a Howard Hughes Medical Institute investigator at UT Southwestern.
Other UT Southwestern researchers involved in the study were Dr. Katsuhiko Tabuchi, instructor of neuroscience; Dr. Jacqueline Blundell, postdoctoral researcher in neurology; Mark Etherton, medical student; Dr. Robert Hammer, professor of biochemistry and in the Cecil H. and Ida Green Center for Reproductive Biology Sciences; Dr. Xinran Liu, assistant professor of neuroscience and molecular genetics; and Dr. Craig Powell, assistant professor of neurology and psychiatry.
The work was supported by the National Institutes of Health, HHMI and Autism Speaks.
Media Contact: Aline McKenzie
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Autistic people have fought the inclusion of ABA in therapy for us since before Autism Speaks, and other non-Autistic-led autism organizations, started lobbying legislation to get it covered by insurances and Medicaid.
ABA is a myth originally sold to parents that it would keep their Autistic child out of an institution. Today, parents are told that with early intervention therapy their child will either be less Autistic or no longer Autistic by elementary school, and can be mainstreamed in typical education classes. ABA is very expensive to pay out of pocket. Essentially, Autism Speaks has justified the big price tag up front will offset the overall burden on resources for an Autistic’s lifetime. The recommendation for this therapy is 40 hours a week for children and toddlers.
The original study that showed the success rate of ABA to be at 50% has never been replicated. In fact, the study of ABA by United States Department of Defense was denounced as a failure. Not just once, but multiple times. Simply stated: ABA doesn’t work. In study after repeated study: ABA (conversion therapy) doesn’t work.
What more recent studies do show: Autistics who experienced ABA therapy are at high risk to develop PTSD and other lifelong trauma-related conditions. Historically, the autism organizations promoting ABA as a cure or solution have silenced Autistic advocates’ opposition. ABA is also known as gay conversion therapy.
The ‘cure’ for Autistics not born yet is the prevention of birth.
The ‘cure’ is a choice to terminate a pregnancy based on ‘autism risk.’ The cure is abortion. This is the same ‘cure’ society has for Down Syndrome.
This is eugenics 2021. Instead of killing Autistics and disabled children in gas chambers or ‘mercy killings’ like in Aktion T4, it’ll happen at the doctor’s office, quietly, one Autistic baby at a time. Different approaches yes, but still eugenics and the extinction of an entire minority group of people.
Fact: You can’t cure Autistics from being Autistic.
Fact: You can’t recover an Autistic from being Autistic.
Fact: You can groom an Autistic to mask and hide their traits. Somewhat. … however, this comes at the expense of the Autistic child, promotes Autistic Burnout (this should not be confused with typical burnout, Autistic Burnout can kill Autistics), and places the Autistic child at high risk for PTSD and other lifelong trauma-related conditions.