Present at birth
For autosomal recessive disorders, dogs with two copies of the variant are at risk of developing the condition. Dogs with one copy of the variant are considered carriers and are usually not at risk of developing the disorder. However, carriers of some complex variants grouped in this category may be associated with a low risk of developing the disorder. Individuals with one or two copies may pass the disorder-associated variant to their puppies if bred.
At risk dogs are highly likely to show signs of this disease in their lifetime.
Partner with your veterinarian to make a plan regarding your dog’s well-being, including any insights provided through genetic testing. If your pet is at risk or is showing signs of this disorder, then the first step is to speak with your veterinarian.
Clinical signs of the disease appear at a few weeks of age with difficulty in ambulation, short-strided gait, and atrophied muscles. Some affected puppies have severe clinical signs from birth and are euthanized in their first weeks of life. Puppies may also have difficulties swallowing, increased salivation, or present with frequent regurgitation. Clinical signs progress leading to severe muscle weakness before 2 years of age. The prognosis for the disease is poor.
As affected dogs have movement difficulties, they will need assistance with everyday tasks. Clinical signs should be monitored as the disorder progresses to best care for the welfare needs of affected dogs. More severely affected dogs are often euthanized on welfare grounds.
There are many responsibilities to consider when breeding dogs. Regardless of test results it is important that your dog is in good general health and that you are in a position to care for the puppies if new responsible owners are not found. For first time or novice breeders, advice can be found at most kennel club websites.
This disease is autosomal recessive meaning that two copies of the mutation are needed for disease signs to occur. A carrier dog with one copy of the Muscular Dystrophy mutation can be safely bred with a clear dog with no copies of the Muscular Dystrophy mutation. About half of the puppies will have one copy (carriers) and half will have no copies of the Muscular Dystrophy mutation. Puppies in a litter which is expected to contain carriers should be tested prior to breeding. Carrier to carrier matings are not advised as the resulting litter may contain affected puppies. Please note: It is possible that disease signs similar to the ones caused by the Muscular Dystrophy mutation could develop due to a different genetic or clinical cause.
All coordinates reference CanFam3.1
Steffen, F., Bilzer, T., Brands, J., Golini, L., Jagannathan, V., Wiedmer, M., … Leeb, T. (2015). A nonsense variant in COL6A1 in landseer dogs with muscular dystrophy. G3: Genes, Genomes, Genetics, 5(12), 2611–2617. View the article