GENETIC TESTING
Degenerative Myelopathy (DM) is a progressive disease of the spinal cord in some older dogs. The disease has an insidious onset typically between the age of 8 and 14 years old. It begins with a loss of coordination (ataxia) in the hind limbs. The affected dog will wobble when walking or drag their feet. This can first occur in one hind limb and then affect the other. As the disease progresses, the limbs become weak and the dog begins to buckle and has difficulty standing. The weakness gets progressively worse until the dog is unable to walk. The clinical course can range from 6 months to 1 year before dogs become paraplegic. If signs progress for a longer period of time, loss of urinary and fecal incontinence may occur and eventually weakness will develop in the front limbs. Another key feature of DM is that it is mercifully not a painful disease.
Exercise-Induced Collapse (EIC) is an inherited neuromuscular disorder affecting Pembroke Welsh Corgis. EIC presents as exercise intolerance in apparently healthy dogs. Affected dogs are usually diagnosed before two years of age and appear normal during low to moderately strenuous activity. However, shortly after 5-20 minutes of strenuous exercise affected dogs will begin to walk with a wobbly, uncoordinated gait that often only affects the hind limbs. Dogs remain mentally alert and are not in pain during episodes of EIC. In some circumstances, the symptoms of EIC can progress to full body weakness with low muscle tone (flaccid paralysis), confusion, loss of consciousness, seizures and very rarely, death. The episodes typically last 5-10 minutes and most dogs will completely recover within 15-30 minutes.
Von Willebrand Disease (vWD) is a genetic disorder that prevents normal blood clotting and can cause extended bleeding following injury or surgery. The disorder results from a deficiency or lack of sufficient von Willebrand factor (vWf) which functions as a binding protein during blood clotting. Three types of vWD have been identified in dogs to date and are known as vWD type 1, 2 and 3. Von Willebrand's Disease type 1 (vWD1) results in reduction in normal levels of vWf to approximately 5-10% of normal. Since some vWf is produced in dogs homozygous for the vWD1 mutations, this form of the disorder is considered to be less serious than type 2 and 3. The mutation (G >A substitution) has variable penetrance and is recessive requiring two copies of the mutation in affected dogs. Typical symptoms of the disease encompass exessive or abnormal bleeding following injury or the presence of blood in various secretions (urine, feces, etc.)
The tests will provide one of three results for breeders testing their dogs:
1.) CLEAR - dog does NOT HAVE the mutated gene; therefore, cannot pass it on or get the disease.
2.) CARRIER - dog has one copy of the mutated gene and can pass it on but NOT get the disease.
3) "AT RISK" - dog has two copies of the gene and stands a risk of actually developing the disease as well as passing it on to offspring.
An "At Risk" test result, however, does not guarantee the dog WILL develop the disease. Research is continuing, hoping to discover what "triggers" the gene to cause the disease to develop.
We are in an ongoing process to test all of our breeding stock. We will post the results as they are released. At that time, if we need to contact previous puppy buyers of possible genetic issues, we will do so. We will do our part to make the best breeding decisions to not produce a dog with both genes at risk to develop this horrid disease.
