An incurable, paralyzing disease in humans is now genetically linked to a similar disease in dogs.
Researchers from the University of Missouri and the Broad Institute have found that the genetic mutation responsible for degenerative myelopathy (DM) in dogs is the same mutation that causes amyotrophic lateral sclerosis (ALS), the human disease also known as Lou Gehrig's Disease.
As a result of the discovery, which will be published in the Proceedings of the National Academy of Sciences this week, researchers can now use dogs with DM as animal models to help identify therapeutic interventions for curing the human disease, ALS.
"We uncovered the genetic mutation of degenerative myelopathy, which has been unknown for 30 years, and linked it to ALS, a human disease that has no cure," said Joan Coates, a veterinary neurologist and associate professor of veterinary medicine and surgery in the MU College of Veterinary Medicine. "Dogs with DM are likely to provide scientists with a more reliable animal model for ALS. Also, this discovery will pave the way for DNA tests that will aid dog breeders in avoiding DM in the future."
Previously, ALS research has relied heavily on transgenic rodents that expressed the mutant human gene SOD1, which causes ALS. Researchers found that dogs with DM also had mutations in their SOD1 gene. Many rodent models possess very high levels of the SOD1 protein that can produce pathologic processes distinct from those occurring in ALS patients. Since the SOD1 mutation is spontaneous in dogs, the clinical spectrum in dogs may represent more accurately that of human ALS.