Genetics

Common Form Of Autism Recreated In New Mouse Model

Source: 
Medical News Today
Date Published: 
October 7, 2011
Abstract: 

Research team from Beth Israel Deaconess Medical Center (BIDMC) has created a genetically engineered mouse with increased dosages of the Ube3 gene. And, like the patients who also harbor increased dosages of this single gene, the genetically engineered mice exhibit robust examples of all three traits considered hallmarks of autism: reduced social interaction, impaired communication and excessive repetitive behaviors. Findings provide further clues in understanding the brain defects that lead to the development of autism, and offer an important tool for future use by scientists and clinicians to test possible drug therapies.

Evidence found for the genetic basis of autism: Models of autism show that gene copy number controls

Source: 
Science Daily
Date Published: 
October 5, 2011
Abstract: 

Scientists at Cold Spring Harbor Laboratory (CSHL) have discovered that one of the most common genetic alterations in autism -- deletion of a 27-gene cluster on chromosome 16 -- causes autism-like features. By generating mouse models of autism using a technique known as chromosome engineering, CSHL Professor Alea Mills and colleagues provide the first functional evidence that inheriting fewer copies of these genes leads to features resembling those used to diagnose children with autism.

Absence of CNTNAP2 Leads to Epilepsy, Neuronal Migration Abnormalities, and Core Autism-Related Deficits

Source: 
Cell
Date Published: 
September 30, 2011
Year Published: 
2011

A new mouse model of autism, created by eliminating a gene strongly associated with the disorder in humans, shows promise for understanding the biology that underlies ASD and testing new treatments. By eliminating the CNTNAP2 gene (contactin associated protein-like 2), researchers were able to create mice with behaviors that closely mimicked those of its human counterparts – the mice exhibited repetitive behaviors, abnormal social interactions, and irregular vocalizations, in addition to experiencing seizures and hyperactivity. CNTNAP2 is thought to play an important role in the development of language, and variants of the gene have been linked to an increased risk of autism and epilepsy. Prior to experiencing seizures, the mice showed signs of abnormal brain circuit development – researchers observed irregularities in communication between neurons and their migration within the brain. These observations complement earlier studies suggesting that children with autism carrying a CNTNAP2 variant have a "disjointed brain." The frontal lobe is poorly connected with the rest of the brain but shows an overconnection with itself, resulting in poor communication with other brain regions. Notably, the mice in the study responded positively to risperidone, an antipsychotic medication approved by the FDA to treat symptoms of irritability and aggression associated with ASD. While their social interactions did not improve – risperidone has not been shown to improve social function in humans – there was a marked improvement in repetitive grooming and a decrease in hyperactivity. Creating an animal model of autism that closely resembles the symptoms and behaviors in humans may be an important tool in understanding neural development in autism and developing new treatments.

--IACC 2011 Summary of Advances in ASD Research

'Autistic' mice created – and treated

Source: 
New Scientist
Date Published: 
October 3, 2011
Abstract: 

A new strain of mice engineered to lack a gene with links to autism displays many of the hallmarks of the condition. It also responds to a drug in the same way as people with autism, which might open the way to new therapies for such people.

Animal Model Research Could Lead To The Development Of Diagnostic Tests For Autism Based On Biomarkers

Source: 
Medical News Today
Date Published: 
September 14, 2011
Abstract: 

The first transgenic mouse model of a rare and severe type of autism called Timothy Syndrome is improving the scientific understanding of autism spectrum disorder in general and may help researchers design more targeted interventions and treatments.

Children With Autism And Gastrointestinal Symptoms Have Altered Digestive Genes

Source: 
Medical News Today
Date Published: 
September 11, 2011
Abstract: 

Researchers at the Center for Infection and Immunity (CII) at Columbia University's Mailman School of Public Health and at the Harvard Medical School report that children with autism and gastrointestinal disturbances have altered expression of genes involved in digestion. These variations may contribute to changes in the types of bacteria in their intestines.

US researchers' discovery promises answers on autism

Source: 
The Australian
Date Published: 
September 8, 2011
Abstract: 

Researchers have for the first time identified two biologically different strains of autism in a major breakthrough being compared with the discovery of different forms of cancer in the 1960s. The findings, to be announced at an international autism conference in Perth today, are seen as a key step towards understanding the causes of autism and developing effective treatments as well as a cure. The findings bring hope that the communication, socialization and other difficulties that autistic children experience can be tackled more easily and earlier.

Attention deficit, autism share genetic risk factors

Source: 
SFARI
Date Published: 
August 22, 2011
Abstract: 

People with autism and attention deficit hyperactivity disorder (ADHD) share some of the same underlying genetic risk factors, according to a study published this month in Science Translational Medicine. This is one of the first studies to find risk variants that are common to both disorders.
In searching for rare copy number variations (CNVs) — deletions and duplications in genetic material — in people with ADHD, the researchers found more than a dozen regions that include genes implicated in bipolar disorder, schizophrenia, intellectual disability and autism.

Autism Risk for Siblings Higher Than Expected

Source: 
New York Times - Well Blog
Date Published: 
August 16, 2011
Abstract: 

According to a recent study published in the journal of Pediatrics, the younger sibling of a child with autism has nearly 20 times greater risk of developing autism than a child in the general population.

Recurrence Risk for Autism Spectrum Disorders: A Baby Siblings Research Consortium Study

Source: 
Pediatrics, Ozonoff et al.
Date Published: 
August 2011
Year Published: 
2011

A study published August 15, 2011 in the journal Pediatrics found that infants with an older autistic sibling have a near 19 percent risk that they too will develop the disorder. The study is considered the largest autism study to follow infants for sibling recurrence.