The Minneapolis based StarTribune.com reported yesterday that researchers at the University of Minnesota have identified the gene mutation responsible for Excercise Induced Collapse (EIC) in Labrador Retrievers. EIC, whose signs include wobbliness sometimes progressing to collapse in the rear legs, sometimes loss of muscle control spreading to the rear legs as well, and in rare cases, death, affects about 3-5 percent of Labs.
A mutation of a gene, known as dynamin 1, produces a protein involved in the chemical signaling system between nerves that allows the brain to control muscle movement. The authors of the study believe that the mutant protein hinders the ability to send signals between nerves, suggesting that EIC occurs because the signaling system can't keep up with the rapid firing required during intense exercise. Like other recessive genetic disorders, 2 copies of the gene are required to exert a clinical effect.
Previously, veterinarians had a significant challenge in arriving at a diagnosis of EIC, because other causes for collapse had to be ruled out. According to StarTribune.com, however, this disease can now be detected with a simple and inexpensive DNA test.
The implications of this discovery are very important. Since all mammals carry dynamin 1, learning more about how the gene's protein functions may potentially contribute to understanding disorders in other mammals, including humans. Regarding animal health primarily, not only can a diagnosis of EIC now be attained much more easily, but breeders can now test potential breeding animals for carrying the mutant gene. This type of genetic screening can go a long way to significantly lowering the incidence of this disease in Labs.
Roger Welton, DVM