Dogs Help to Find and Cure Rare Human Disease
By: Dr. Jack Stephens
At the University of Missouri-Columbia, Tibetan terriers are contributing to a canine DNA bank in an ongoing research program that studies the genetic basis of a neurological disease that affects both dogs and humans.
The disease is neuronalceroid lipofuscinoisis (NCL) in dogs and Batten disease in humans. A rare, inherited neurological disorder, NCL/Batten disease does not currently have a cure. According to Dr. Martin Katz, professor of ophthalmology with a dual appointment in the School of Medicine and the College of Veterinary Medicine, human NCL often goes misdiagnosed due to its rarity and symptoms that are similar to other diseases. Affected children develop symptoms that may include blindness, seizures, cognitive decline and loss of motor function.
But Dr. Katz feels the purebred Tibetan terrier may hold the key for the genetic basis of the disease. By comparing the mutated genes of affected dogs to unaffected dogs, researchers have been able to pinpoint the mutant gene and identify through a complicated mapping process where the gene is in the DNA sequence.
A simple test for the mutation can then be performed on any dog using DNA extracted from a blood sample. This test will enable breeders to screen dogs prior to breeding to prevent future generations from being affected. This process will also lead to making it possible to determine whether any humans with NCL have the same mutations in the corresponding human genes.
The shorter life span of a dog allows researchers to conduct their studies much faster than with people, and the similarity of the disease will allow for better and faster results for humans. Another benefit of studying the genes in dogs is that there is excellent record keeping by the breed registries and close observations by the dog owners, which make them ideal subjects for genetic studies.
Another way man’s best friend continues to help us.
Source: Veterinary Medical Review, College of Veterinary Medicine, University of Missouri.