Comprehensive Guide to Degenerative Myelopathy Testing in Dogs

Degenerative myelopathy (DM) is a progressive neurological disease in dogs characterised by the gradual loss of coordination and strength, initially affecting the hind limbs and potentially progressing to paralysis. This hereditary condition is caused by mutations in the SOD1 gene and occurs in 43 recognised pedigree dog breeds, although its impact varies widely among them. Responsible breeders and owners can benefit greatly from understanding and utilising testing schemes to reduce the prevalence of DM in future generations.

Understanding Canine Degenerative Myelopathy

DM primarily affects the spinal cord, causing a progressive weakening and loss of coordination in a dog’s hind legs. Symptoms often begin with dragging or scuffing of one or both hind paws and general weakness, which can escalate over months to years into paralysis. In advanced stages, the condition can affect the front limbs, cranial nerves, and respiratory muscles. Due to its incurable nature, humane euthanasia is often considered when the dog’s quality of life is severely compromised.

The age of onset is usually around seven to eight years or older, making early detection challenging as many affected dogs may already have been bred before symptoms appear. The speed of progression varies; some dogs may experience paralysis within a year of symptom onset, whereas others progress more slowly.

Which Breeds Are Most At Risk?

While the SOD1 gene mutation is found in many breeds, significant risk is concentrated in a smaller set, including but not limited to the French Bulldog puppies, German Shepherd puppies, Pembroke Welsh Corgi puppies, and Boxer puppies. For these breeds, health screening is particularly important to prevent affected dogs from passing the mutation on to offspring.

How Does Degenerative Myelopathy Inherit?

DM is inherited via an autosomal recessive pattern, meaning a dog must inherit two copies of the mutated SOD1 gene—one from each parent—to be at high risk of developing the disease. Dogs with only one copy are carriers and typically do not show symptoms but can pass the mutation to their puppies.

Breeding two clear dogs results in litters free from DM genes, while breeding two affected dogs means all offspring will be at risk. Various combinations involving carriers can produce mixed litters, so testing is essential to understand and manage the genetic makeup of breeding pairs responsibly.

How to Get Your Dog Tested for DM

Testing your dog for degenerative myelopathy is a crucial step, especially for breeders or owners of at-risk breeds. Due to the late onset of symptoms, a dog might appear healthy but still carry or be affected by the mutation.

Step 1: Consult Your Vet

Request a DM genetic test for your dog. Your vet can collect a DNA sample via a simple blood draw or a buccal (cheek) swab, both minimally invasive.

Step 2: Laboratory Testing

The sample is sent to an approved laboratory for analysis. Testing typically takes 7 to 10 working days, with costs around £50 to £70, depending on your provider.

Step 3: Receive and Interpret Results

Results will classify your dog as Clear (no gene mutation), Carrier (one mutated gene), or Affected (two mutated genes). This information helps breeders make ethical breeding decisions and owners anticipate potential care needs.

For approved laboratories, check The Kennel Club’s official list.

Why Responsible Breeding Matters

By ensuring dogs tested clear or not breeding affected animals, breeders can reduce the incidence of DM. Responsible breeding preserves the health and welfare of future generations and demonstrates commitment to ethical standards in dog breeding.

Summary and Next Steps

Degenerative myelopathy testing is a vital tool in safeguarding canine health, particularly for breeds at higher risk. Early genetic testing, combined with veterinary assessment, supports informed decisions that can curb the spread of this debilitating disease.

If you plan to get a new puppy, searching for reputable puppies and discussing health tests with breeders ensures a healthier start for your new companion.

Ultimately, knowledge empowers dog owners and breeders to act responsibly, improving quality of life for dogs and reducing hereditary disease prevalence.