They said their achievement offers the potential for treatment of the disorder, the most common form of inherited mental retardation and a leading identified genetic cause of autism. There is currently no treatment or therapy for fragile X syndrome, whose symptoms include mental retardation, epilepsy, and abnormal body growth.
Mark Bear and colleagues reported their findings in an article in the December 20, 2007, issue of the journal Neuron, published by Cell Press.
Fragile X syndrome is known to be caused by loss of the gene for “fragile X mental retardation protein” (FMRP), which is believed to act as a brake on protein synthesis in specific areas of brain circuitry. The authors’ idea was that loss of the “brake” would allow another protein that stimulates this process, called metabotropic glutamate receptor 5 (mGluR5), to function unchecked.
In their experiments to test this idea, the researchers studied mice that produce many of the characteristic pathologies of fragile X in humans due to a loss of the FMRP gene. The critical test, though, was when they also created double mutant mice that lacked both the FMRP gene and had a 50% reduction in mGluR5. They chose only to reduce the activity of the metabotropic glutamate receptor gene, rather than eliminate it, in order to reflect what might be achieved using drug treatment for fragile X in humans.
Their tests on the double mutant mice revealed that the mGluR5 gene reduction greatly alleviated many abnormalities produced by loss of FMRP. The double mutant mice showed a rescue of abnormalities in brain structure and function, brain protein synthesis, memory, and body growth.
For example, loss of the FMRP gene produces overgrowth of the connections among neurons called dendritic spines. However, the additional 50% reduction in mGluR5 gene produced mice with completely normal spine density.
The double mutants also showed substantial reduction in epileptic seizures caused by lack of FMRP, found the researchers.
They concluded that “it is remarkable that by reducing mGluR5 gene dosage by 50%, we were able to bring multiple, widely varied fragile X phenotypes significantly closer to normal.”
They also concluded that “These findings have major therapeutic implications for fragile X syndrome and autism.”
Cathleen Genova | EurekAlert!
Complementing conventional antibiotics
24.05.2018 | Goethe-Universität Frankfurt am Main
Building a brain, cell by cell: Researchers make a mini neuron network (of two)
23.05.2018 | Institute of Industrial Science, The University of Tokyo
A research team led by physicists at the Technical University of Munich (TUM) has developed molecular nanoswitches that can be toggled between two structurally different states using an applied voltage. They can serve as the basis for a pioneering class of devices that could replace silicon-based components with organic molecules.
The development of new electronic technologies drives the incessant reduction of functional component sizes. In the context of an international collaborative...
At the LASYS 2018, from June 5th to 7th, the Laser Zentrum Hannover e.V. (LZH) will be showcasing processes for the laser material processing of tomorrow in hall 4 at stand 4E75. With blown bomb shells the LZH will present first results of a research project on civil security.
At this year's LASYS, the LZH will exhibit light-based processes such as cutting, welding, ablation and structuring as well as additive manufacturing for...
There are videos on the internet that can make one marvel at technology. For example, a smartphone is casually bent around the arm or a thin-film display is rolled in all directions and with almost every diameter. From the user's point of view, this looks fantastic. From a professional point of view, however, the question arises: Is that already possible?
At Display Week 2018, scientists from the Fraunhofer Institute for Applied Polymer Research IAP will be demonstrating today’s technological possibilities and...
So-called quantum many-body scars allow quantum systems to stay out of equilibrium much longer, explaining experiment | Study published in Nature Physics
Recently, researchers from Harvard and MIT succeeded in trapping a record 53 atoms and individually controlling their quantum state, realizing what is called a...
The historic first detection of gravitational waves from colliding black holes far outside our galaxy opened a new window to understanding the universe. A...
02.05.2018 | Event News
13.04.2018 | Event News
12.04.2018 | Event News
24.05.2018 | Ecology, The Environment and Conservation
24.05.2018 | Medical Engineering
24.05.2018 | Physics and Astronomy