Researchers identify genetic mutation causing rare form of spinal muscular atrophy

May 10, 2012

Scientists have confirmed that mutations of a gene are responsible for some cases of a rare, inherited disease that causes progressive muscle degeneration and weakness: spinal muscular atrophy with lower extremity predominance, also known as SMA-LED.

"Typical spinal muscular atrophies begin in or early childhood and are fatal, involving all motor neurons, but SMA-LED predominantly affects controlling muscles of the legs. It is not fatal and the prognosis is good, although patients usually are moderately disabled and require assistive devices such as bracing and wheelchairs throughout their lives," said Robert H. Baloh, MD, PhD, director of Cedars-Sinai Medical Center's Neuromuscular Division and senior author of a Neurology article describing the new findings on DYNC1H1.

It is a molecule inside cells that acts as a motor to transport . Using cells cultured from patients, Baloh's group showed that the mutation disrupts this motor's function. The researchers found that some subjects with mutations had global developmental delay in addition to weakness, indicating the brain also is involved.

"Our observations suggest that a range of DYNC1H1-related disease exists in humans – from a widespread neurodevelopmental abnormality of the central nervous system to more selective involvement of certain motor neurons, which manifests as ," Baloh said.

He pointed out that while this molecule is responsible for some inheritable cases of spinal muscular atrophy with lower extremity predominance, the genetic mutation is absent in others. The search continues, therefore, to find other culprit genetic and develop biological therapies to correct them.

"Although this is a rare form of motor neuron disease, it tells us that dynein function – the molecular motor – is crucial for the development and maintenance of , which we hope will provide insight into the common form of spinal muscular atrophy and also amyotrophic lateral sclerosis," Baloh said. ALS (also known as Lou Gehrig's disease) is a progressive neurodegenerative disease that affects nerve cells in the brain and spinal cord.

Baloh, an expert in treating and studying neuromuscular and neurodegenerative diseases, joined Cedars-Sinai in early 2012, working with other physicians and scientists in the Department of Neurology and the Regenerative Medicine Institute to establish one of the most comprehensive neuromuscular disease treatment and research teams in California.

Explore further: Researchers find new insight into spinal muscular atrophy

More information: Citation: Neurology, March 28, 2012, published online ahead of print: "Mutations in the tail domain of DYNC1H1 cause dominant spinal muscular atrophy."

Related Stories

Researchers find new insight into spinal muscular atrophy

September 26, 2011
Researchers at the University of Missouri have identified a communication breakdown between nerves and muscles in mice that may provide new insight into the debilitating and fatal human disease known as spinal muscular atrophy ...

Recommended for you

Researchers find monkey brain structure that decides if viewed objects are new or unidentified

August 18, 2017
A team of researchers working at the University of Tokyo School of Medicine has found what they believe is the part of the monkey brain that decides if something that is being viewed is recognizable. In their paper published ...

Artificial neural networks decode brain activity during performed and imagined movements

August 18, 2017
Artificial intelligence has far outpaced human intelligence in certain tasks. Several groups from the Freiburg excellence cluster BrainLinks-BrainTools led by neuroscientist private lecturer Dr. Tonio Ball are showing how ...

Study of nervous system cells can help to understand degenerative diseases

August 18, 2017
The results of a new study show that many of the genes expressed by microglia differ between humans and mice, which are frequently used as animal models in research on Alzheimer's disease and other neurodegenerative disorders.

How whip-like cell appendages promote bodily fluid flow

August 18, 2017
Researchers at Nagoya University have identified a molecule that enables cell appendages called cilia to beat in a coordinated way to drive the flow of fluid around the brain; this prevents the accumulation of this fluid, ...

Researchers make surprising discovery about how neurons talk to each other

August 17, 2017
Researchers at the University of Pittsburgh have uncovered the mechanism by which neurons keep up with the demands of repeatedly sending signals to other neurons. The new findings, made in fruit flies and mice, challenge ...

Neurons involved in learning, memory preservation less stable, more flexible than once thought

August 17, 2017
The human brain has a region of cells responsible for linking sensory cues to actions and behaviors and cataloging the link as a memory. Cells that form these links have been deemed highly stable and fixed.

0 comments

Please sign in to add a comment. Registration is free, and takes less than a minute. Read more

Click here to reset your password.
Sign in to get notified via email when new comments are made.