Scientists Discover Gene Appears to Influence How Long People Live with ALS
According to a new study published on August 26 in Nature Medicine, scientists have discovered a gene that influences how long people live with ALS. The international team that made the discovery was led by Wim Robberecht, M.D., of University Hospital in Leuven, Belgium.
ALS occurs when motor neurons degenerate. During the early stages of the disease, the long extensions that motor neurons use to communicate with other cells, called axons, die back. Researchers believe these axons regrow initially, and only later die off completely. Signals emanating from nearby cells guide the axons during this regrowth.
The newly discovered gene, called Epha4, is used by the motor neurons to create a receptor for these guidance signals. In animal models of ALS, researchers found that preventing motor neurons from making this receptor, or blocking it using a drug, delayed the onset of disease and prolonged life.
“This discovery reveals a new and potentially important pathway affecting motor neurons that we may be able to target for new therapies,” said Lucie Bruijn, Ph.D., Chief Scientist for The ALS Association. “Being able to support motor neurons that are in the process of degenerating could be a valuable strategy for treatment, and may eventually lead to helping people live longer with the disease.”
Because it seems to be involved in a number of different neurodegenerative pathways, it may allow us to develop treatments for ALS due to multiple different causes, and thus for many different patients.”
The importance of the gene in humans with ALS was confirmed in the same study by examining the amount of Epha4 in almost 3000 ALS patients. Those who had lower levels of Epha4 tended to have later disease onset and longer survival. Researchers will now be trying to determine how the reduction of Epha4 protects motor neurons and how to develop treatments that augment this effect.