Featured Research

from universities, journals, and other organizations

Scientists Create First Animal Model Of Rett Syndrome

Date:
March 7, 2001
Source:
Whitehead Institute For Biomedical Research
Summary:
Researchers from the Whitehead Institute for Biomedical Research have created the long-awaited animal model for Rett syndrome, one of the most common causes of mental retardation in females with an incidence of 1 in 10,000-15,000. The transgenic mouse model sheds much-needed light on the underlying mechanism of the disease and suggests a new reason for hope in the research toward therapies.

Researchers from the Whitehead Institute for Biomedical Research have created the long-awaited animal model for Rett syndrome, one of the most common causes of mental retardation in females with an incidence of 1 in 10,000-15,000. The transgenic mouse model sheds much-needed light on the underlying mechanism of the disease and suggests a new reason for hope in the research toward therapies.

Rett syndrome, caused by a defective gene on the X-chromosome, is thought to have a lethal effect in males before birth or shortly after. Girls with Rett syndrome (and two copies of the X chromosome) are healthy babies who develop normally until six to eighteen months old. But then something goes terribly wrong—their health deteriorates and they begin to show symptoms such as loss of speech, loss of voluntary motor control, constant hand wringing, and seizures.

The work, published in the March 2001 issue of Nature Genetics from Rudolf Jaenisch and colleagues, suggests that the genetic defect underlying Rett syndrome has an effect not only during brain development before birth but has critical prolonged effects even after birth. Since it is easier to treat newborns than to correct defects in embryonic development, these findings may hold promise for future therapies.

In 1999, scientists from the Baylor College of Medicine in Houston, Texas, found that mutations in a gene called MECP2 were responsible for Rett syndrome. However, the exact mechanism by which mutated MECP2 brings about the mental deterioration was unknown.

The Jaenisch lab was able to use its expertise in transgenic technology to create mice in which the Mecp2 gene could be disrupted at any time during their development before or after birth. To the researchers’ surprise, male mice lacking Mecp2 did not die and showed a less severe syndrome. The male mice developed Rett-like symptoms, but survived to young adulthood, and females remained healthy well into adulthood. Similarities between the brains of mutant mice and Rett patients—small brains and small neurons—indicate that comparable brain and neuronal changes are occurring in both species. These mice, therefore, serve as good models for the disease.

Researchers previously hypothesized that Rett syndrome might result from widespread defects during embryonic development effecting the brain and possibly other organs. Though the Mecp2 gene is expressed throughout the body, the researchers found that the Rett-like symptoms in mice were caused by brain malfunction rather than problems of Mecp2 deficiency in the rest of the body.

Contrary to previous theories, the authors also indicate that the role of Mecp2 is not limited to the development of the brain before birth, but is also critical in the maintenance of mature neurons after birth. This suggests that therapeutic strategies could be aimed at preventing the development of postnatal defects in neurons, rather than at correcting neuronal deficiencies that existed before birth.


Story Source:

The above story is based on materials provided by Whitehead Institute For Biomedical Research. Note: Materials may be edited for content and length.


Cite This Page:

Whitehead Institute For Biomedical Research. "Scientists Create First Animal Model Of Rett Syndrome." ScienceDaily. ScienceDaily, 7 March 2001. <www.sciencedaily.com/releases/2001/03/010305071923.htm>.
Whitehead Institute For Biomedical Research. (2001, March 7). Scientists Create First Animal Model Of Rett Syndrome. ScienceDaily. Retrieved October 21, 2014 from www.sciencedaily.com/releases/2001/03/010305071923.htm
Whitehead Institute For Biomedical Research. "Scientists Create First Animal Model Of Rett Syndrome." ScienceDaily. www.sciencedaily.com/releases/2001/03/010305071923.htm (accessed October 21, 2014).

Share This



More Health & Medicine News

Tuesday, October 21, 2014

Featured Research

from universities, journals, and other organizations


Featured Videos

from AP, Reuters, AFP, and other news services

CDC Revamps Ebola Guidelines After Criticism

CDC Revamps Ebola Guidelines After Criticism

Newsy (Oct. 21, 2014) The Centers for Disease Control and Prevention have issued new protocols for healthcare workers interacting with Ebola patients. Video provided by Newsy
Powered by NewsLook.com
WHO: Ebola Vaccine Trials to Start a in January

WHO: Ebola Vaccine Trials to Start a in January

AP (Oct. 21, 2014) Tens of thousands of doses of experimental Ebola vaccines could be available for "real-world" testing in West Africa as soon as January as long as they are deemed safe in soon to start trials, the World Health Organization said Tuesday. (Oct. 21) Video provided by AP
Powered by NewsLook.com
First-Of-Its-Kind Treatment Gives Man Ability To Walk Again

First-Of-Its-Kind Treatment Gives Man Ability To Walk Again

Newsy (Oct. 21, 2014) A medical team has for the first time given a man the ability to walk again after transplanting cells from his brain onto his severed spinal cord. Video provided by Newsy
Powered by NewsLook.com
CDC Issues New Ebola Guidelines for Health Workers

CDC Issues New Ebola Guidelines for Health Workers

Reuters - US Online Video (Oct. 21, 2014) The U.S. Centers for Disease Control and Prevention has set up new guidelines for health workers taking care of patients infected with Ebola. Linda So reports. Video provided by Reuters
Powered by NewsLook.com

Search ScienceDaily

Number of stories in archives: 140,361

Find with keyword(s):
Enter a keyword or phrase to search ScienceDaily for related topics and research stories.

Save/Print:
Share:

Breaking News:

Strange & Offbeat Stories


Health & Medicine

Mind & Brain

Living & Well

In Other News

... from NewsDaily.com

Science News

Health News

Environment News

Technology News



Save/Print:
Share:

Free Subscriptions


Get the latest science news with ScienceDaily's free email newsletters, updated daily and weekly. Or view hourly updated newsfeeds in your RSS reader:

Get Social & Mobile


Keep up to date with the latest news from ScienceDaily via social networks and mobile apps:

Have Feedback?


Tell us what you think of ScienceDaily -- we welcome both positive and negative comments. Have any problems using the site? Questions?
Mobile: iPhone Android Web
Follow: Facebook Twitter Google+
Subscribe: RSS Feeds Email Newsletters
Latest Headlines Health & Medicine Mind & Brain Space & Time Matter & Energy Computers & Math Plants & Animals Earth & Climate Fossils & Ruins