DM

Degenerative Myelopathy is a progressive disease of the spinal cord in older dogs. The disease has an insidious onset typically between 7 and 14 years of age. It begins with a loss of coordination (ataxia) in the hind limbs. As of July 15, 2008 the mutated gene responsible for DM has been found present in 43 breeds including German Shepherds (which are present in the Tamaskan heritage). The disease is chronic and progressive, and results in paralysis.

One proposed cause of degenerative myelopathy is that the immune system attacks this sheath, breaking it down. This results in a loss of communication between nerves in lower body of the animal and the brain. DM initially affects the back legs and causes muscle weakness and loss, and lack of coordination. These cause a staggering effect that may appear to be arthritis (making it easy for a vet to mi-diagnose as old age)

Progression of the disease is generally slow but highly variable. The animal could be crippled within a few months, or may survive up to three years or more. DM is a non-reversible, progressive disease that cannot be cured. There are no treatments that have been clearly shown to stop or slow progression.

The Animal Molecular Genetics Laboratory and the University of Missouri have identified a DNA mutation that is a major risk factor for development of degenerative myelopathy in dogs. A DNA test is now available for use by veterinarians, breeders and pet owners. This test is available through the OFA (Orthopedic Foundation for Animals). The test clearly identifies dogs that are clear (have 2 normal copies of the gene), those who are carriers (have one normal copy of the gene and one mutated copy of the gene), and those who are at much higher risk for developing DM (have 2 mutated copies of the gene). However, having two mutated copies of the gene does not necessarily result in disease. Indeed being a relatively new form of testing many questions have been raised as the the actual accuracy of the test as a large majority of dogs tested positive have not developed the disease.

Two Tamaskan Dogs (from the same litter) were found to be 'at risk' of developing DM leading to several more breeding dogs being tested, so far 4 dogs have been At Risk and many more have been found to be carriers, leading to the genetic testing for DM becoming mandatory. Fortunately none of the At Risk dogs have developed any symptoms, and may never.