Researchers may have found the root cause of a disease called amyotrophic lateral sclerosis, also known as Lou Gehrig's disease.

The serious disease can cause paralysis and death and affects as many as 30,000 Americans, a University of Wisconsin-Madison news release reported.

The researchers spotted an error in protein formation that could cause the disease. The researchers have been studying human motor neurons in a lab.

Researcher  Su-Chun Zhang, a neuroscientist at the Waisman Center at UW-Madison successfully transformed skin cells into iPS (induced pluripotent stem) cells which were then converted into motor neurons.  These IPS  cells can be used as "disease models." 

"[This approach] can only study the results of a known disease-causing gene. With iPS, you can take a cell from any patient, and grow up motor neurons that have ALS. That offers a new way to look at the basic disease pathology," Zhang said in the news release.

The researchers have pinpointed "proteins that build a transport structure inside the motor neurons," the news release reported.

This structure, called a neurofilament, moves chemicals around the nerve cell. Neurotransmitters can be moved up to a yard from their origin to better signal the muscles; if this connections is missing the patient can become paralyzed.
In Lou Gehrig's disease misshapen proteins block passage along nerve fibers causing them to die.  The researchers have now discovered the source of these "tangles."

 "Like the studs, joists and rafters of a house, the neurofilament is the backbone of the cell, but it's constantly changing. These proteins need to be shipped from the cell body, where they are produced, to the most distant part, and then be shipped back for recycling. If the proteins cannot form correctly and be transported easily, they form tangles that cause a cascade of problems," Zhang said. "Our discovery here is that the disease ALS is caused by misregulation of one step in the production of the neurofilament."

The researchers are now using this new information to come up with a drug to treat the dangerous disease.