Navigation Links
Scripps Florida scientists find connection between gene mutation, key symptoms of autism

JUPITER, FL April 25, 2014 Scientists have known that abnormal brain growth is associated with autism spectrum disorder. However, the relationship between the two has not been well understood.

Now, scientists from the Florida campus of The Scripps Research Institute (TSRI) have shown that mutations in a specific gene that is disrupted in some individuals with autism results in too much growth throughout the brain, and yet surprisingly specific problems in social interactions, at least in mouse models that mimic this risk factor in humans.

"What was striking is that these were basically normal animals in terms of behavior, but there were consistent deficits in tests of social interaction and recognitionwhich approximate a major symptom of autism," said Damon Page, a TSRI biologist who led the study. "This suggests that when most parts of the brain are overgrown, the brain somehow adapts to it with minimal effects on behavior in general. However, brain circuits relevant to social behavior are more vulnerable or less able to tolerate this overgrowth."

The study, which focuses on the gene phosphatase and tensin homolog (PTEN), was recently published online ahead of print by the journal Human Molecular Genetics.

Autism spectrum disorder is a neurodevelopmental disorder involving a range of symptoms and disabilities involving social deficits and communication difficulties, repetitive behaviors and interests, and sometimes cognitive delays. The disorder affects in approximately one percent of the population; some 80 percent of those diagnosed are male.

In a previous study, Page and colleagues found that mutations in Pten causes increased brain size and social deficits, with both symptoms being exacerbated by a second "hit" to a gene that regulates levels of the neurotransmitter serotonin in the brain. In the new study, the TSRI team set out to explore whether mutations in Pten result in widespread or localized overgrowth within the brain, and whether changes in brain growth are associated with broad or selective deficits in tests of autism-relevant behaviors in genetically altered mice. The team tested mice for autism spectrum disorder-related behaviors including mood, anxiety, intellectual, and circadian rhythm and/or sleep abnormalities.

The researchers found that Pten mutant mice showed altered social behavior, but few other changesa more subtle change than would have been predicted given broad expression and critical cellular function of the gene.

Intriguingly, some of the more subtle impairments were sex-specific. In addition to social impairments, males with the mutated gene showed abnormalities related to repetitive behavior and mood/anxiety, while females exhibited additional circadian activity and emotional learning problems.

The results raise the question of how mutations in PTEN, a general regulator of growth, can have relatively selective effects on behavior and cognitive development. One idea is that PTEN mutations may desynchronize the normal pattern of growth in key cell typesthe study points to dopamine neuronsthat are relevant for social behavior.

"Timing is everything," Page said. "Connections have to form in the right place at the right time for circuits to develop normally. Circuitry involved in social behavior may turn out to be particularly vulnerable to the effects of poorly coordinated growth."


Contact: Eric Sauter
Scripps Research Institute

Related biology news :

1. Scripps Research discoveries lead to newly approved drug for infant respiratory distress syndrome
2. Scripps Research Institute scientists find promising vaccine targets on hepatitis C virus
3. Scripps Research Institute Professor Gerald F. Joyce elected to American Academy of Arts & Sciences
4. Scripps Research Institute scientists develop antidote for cocaine overdose
5. Scientist wins $3 million renewal of one of longest-running NIH grants to Scripps Research
6. Scripps research scientists find anticonvulsant drug helps marijuana smokers kick the habit
7. Scripps Florida scientist awarded $1.5 million to design therapeutics with new RNA approach
8. Scripps Florida scientists identify neurotranmitters that lead to forgetting
9. Plastic trash altering ocean habitats, Scripps study shows
10. Scripps Florida scientists awarded $8.4 million grant to develop new anti-smoking treatments
11. Esther B. OKeeffe Foundation gives $2 million to the Scripps Research Institute
Post Your Comments:
Related Image:
Scripps Florida scientists find connection between gene mutation, key symptoms of autism
(Date:11/9/2015)... 9, 2015  Synaptics Inc. (NASDAQ: SYNA ), ... broader entry into the automotive market with a comprehensive ... pace of consumer electronics human interface innovation. Synaptics, industry-leading ... for the automotive industry and will be implemented in ... Europe , Japan , and ...
(Date:11/2/2015)... MENLO PARK, Calif. , Nov. 2, 2015 /PRNewswire/ ... to $9 million to provide preclinical development services to ... Under the contract, SRI will provide scientific expertise, modern ... a wide variety of preclinical pharmacology and toxicology studies ... --> --> The PREVENT Cancer Drug ...
(Date:10/29/2015)... Calif. , Oct. 29, 2015  The J. ... new report titled, "DNA Synthesis and Biosecurity: Lessons Learned ... the Department of Health and Human Services guidance for ... in 2010. --> ... it also has the potential to pose unique biosecurity ...
Breaking Biology News(10 mins):
(Date:11/27/2015)... 27, 2015 ... of companion diagnostics is one of the ... with pharmaceutical companies and diagnostic manufacturers working ... . --> ... on global cancer biomarkers market spread across ...
(Date:11/25/2015)... -- 2 nouvelles études permettent d , ... entre les souches bactériennes retrouvées dans la plaque ... . Ces recherches  ouvrent une nouvelle voie ... efficace de l,un des problèmes de santé les ...    --> 2 nouvelles études permettent d ...
(Date:11/25/2015)... ... November 25, 2015 , ... ... of Black Aerospace Professionals (OPBAP) has been formalized with the signing of a ... leaders met with OPBAP leaders Capt. Karl Minter and Capt. Albert Glenn Tuesday, ...
(Date:11/24/2015)... ... , ... The United States Golf Association (USGA) today announced Dr. Bruce Clarke, ... annually since 1961, the USGA Green Section Award recognizes an individual’s distinguished service to ... Clarke, of Iselin, N.J., is an extension specialist of turfgrass pathology in the department ...
Breaking Biology Technology: