Navigation Links
Rare genetic disorder gives clues to autism, epilepsy, mental retardation
Date:9/23/2008

A rare genetic disorder called tuberous sclerosis complex (TSC) is yielding insight into a possible cause of some neurodevelopmental disorders: structural abnormalities in neurons, or brain cells. Researchers in the F.M. Kirby Neurobiology Center at Children's Hospital Boston, led by Mustafa Sahin, MD, PhD, and Xi He, PhD, also found that normal neuronal structure can potentially be restored.

If this could be done safely in humans, it might be possible to ameliorate the symptoms of epilepsy, mental retardation and autism, which are frequent complications of TSC, say the researchers. Their findings, accompanied by commentary, were the cover article of the September 15 issue of Genes & Development.

TSC causes benign tumor-like lesions, which can affect every organ in the body and are called tubers when they occur in the brain. In the study, Sahin, He, lead author Yong-Jin Choi, PhD, and colleagues show in mice that when the two genes linked to the disease, TSC1 and TSC2, are inactivated, neurons grow too many axons (the long nerve fibers that transmit signals). Normal neurons grow just one axon and multiple dendrites (short projections that receive input from other neurons). This specification of axons and dendrites, known as polarity, is crucial for proper information flow.

"We think if initial polarity is not formed properly, the result will be abnormal connectivity in the brain," says Sahin, who also directs the clinical Multi-Disciplinary Tuberous Sclerosis program at Children's.

Since autism occurs in about half of people with TSC, the findings support the idea that such miswiring causes or contributes to autism, Sahin adds. He has received funding from Autism Speaks, the Manton Foundation and the Tuberous Sclerosis Alliance to pursue this idea further.

"People have started to look at autism as a developmental disconnection syndrome there are either too many connections or too few connections between different parts of the brain," Sahin says. "In mouse models of TSC, we're seeing an exuberance of connections."

In laboratory experiments, the researchers were able to limit multiple axon formation by using the cancer drug rapamycin to suppress production of a protein called SAD-A kinase. This protein is produced in excess when the TSC1 and TSC2 genes are inactivated, and is found in abundance in the abnormally large cells that make up tubers.

Because increased SAD-A is associated with increased axon growth, the researchers also speculate that the TSC pathway could be manipulated to regenerate or repair axons lost or damaged in spinal cord or other nerve injuries.

"These findings provide a potential explanation for neurological abnormalities in TSC patients and perhaps in people without TSC," says He. "The challenge remains as to how to treat these conditions. We have some clues but a lot more research needs to be done."


'/>"/>

Contact: James Newton
james.newton@childrens.harvard.edu
617-919-3110
Children's Hospital Boston
Source:Eurekalert

Related biology news :

1. Childrens Hospital researchers identify genetic mutation that may predict organ rejection
2. K-State professors USDA research shows mad cow disease also caused by genetic mutation
3. How do race, genetics and health-care disparities affect spread of HIV?
4. Exploding chromosomes fuel research about evolution of genetic storage
5. Genetics reveals big fish that almost got away
6. Scientists discover major genetic cause of colorectal cancer
7. Seed Wars: Controversies and Cases on Plant Genetic Resources and Intellectual Property
8. Study helps pinpoint genetic variations in European Americans
9. Study finds connections between genetics, brain activity and preference
10. Genetic data promises new future for kiwi fruit
11. Advances in the field of schizophrenia research: New genetic factors identified
Post Your Comments:
*Name:
*Comment:
*Email:
(Date:4/11/2017)... , Apr. 11, 2017 Research and Markets ... 2017-2021" report to their offering. ... The global eye tracking market to grow at a CAGR ... Global Eye Tracking Market 2017-2021, has been prepared based on an ... the market landscape and its growth prospects over the coming years. ...
(Date:4/6/2017)... April 6, 2017 Forecasts by ... Document Readers, by End-Use (Transportation & Logistics, Government & ... Gas & Fossil Generation Facility, Nuclear Power), Industrial, Retail, ... Are you looking for a definitive report ... ...
(Date:4/5/2017)... KEY FINDINGS The global market ... CAGR of 25.76% during the forecast period of 2017-2025. ... for the growth of the stem cell market. ... MARKET INSIGHTS The global stem cell market is segmented ... The stem cell market of the product is segmented ...
Breaking Biology News(10 mins):
(Date:10/9/2017)... , ... October 09, 2017 , ... ... four-tiered line of medical marijuana products targeting the needs of consumers who are ... of Kindred takes place in Phoenix, Arizona. , As operators of two successful ...
(Date:10/7/2017)... ... October 06, 2017 , ... ... and applications consulting for microscopy and surface analysis, Nanoscience Instruments is now ... Analytical offers a broad range of contract analysis services for advanced applications. ...
(Date:10/7/2017)... 6, 2017  The 2017 Nobel Prize in ... Jacques Dubochet, Joachim Frank and ... cryo-electron microscopy (cryo-EM) have helped to broaden ... biology community. The winners worked with systems manufactured ... produce highly resolved, three-dimensional images of protein structures ...
(Date:10/6/2017)... ... 2017 , ... On Tuesday, October 24th, ABC² (Accelerate Brain ... adaptive clinical trial for glioblastoma (GBM). The featured speaker will be Dr. Brian ... to the public, but registration is required. , WHAT: ABC² Brain Cancer ...
Breaking Biology Technology: