The most commonly associated genetic mutation with Degenerative Myelopathy is found in the SOD1 gene, which plays a role in protecting nerve cells from damage. When this gene is mutated, toxic processes build up within the spinal cord, gradually destroying nerve fibers. This degeneration primarily affects the lower spinal cord, which is responsible for hind limb movement, although the disease may eventually progress to other parts of the body in advanced stages.
Clinical signs of DM typically appear in adult or senior dogs, usually after the age of 7 years, although onset can vary depending on breed and genetic factors. Early symptoms often include mild hind limb weakness, difficulty rising, dragging of the paws, and occasional stumbling. As the disease progresses, dogs may develop muscle wasting, loss of coordination, knuckling of the paws, and a noticeable scuffing of the nails due to improper foot placement. Over time, hind limb paralysis can occur, eventually progressing to the front limbs in severe cases. Despite the physical decline, DM is generally not painful.
The DM DNA Health Test is designed to detect the specific mutation in the SOD1 gene associated with Degenerative Myelopathy. Testing is simple, safe, and non-invasive, typically requiring a cheek swab or blood sample. The sample is analyzed in a specialized laboratory to determine the dog's genetic status. Since DNA does not change throughout life, testing can be performed at any age, including in young puppies before any clinical signs are visible.
Results are generally reported in one of three categories:
- Clear (Normal): The dog does not carry the SOD1 mutation and is not at risk of developing genetic DM or passing the mutation to offspring.
- Carrier: The dog carries one copy of the mutation but is typically not expected to develop Degenerative Myelopathy. However, it can pass the mutation to future generations.
- At Risk (Two Copies): The dog carries two copies of the mutation and has a significantly increased likelihood of developing Degenerative Myelopathy later in life.
It is important to note that while dogs with two copies of the mutation are considered genetically at risk, not all of them will develop clinical disease, as other genetic and environmental factors may also influence onset and progression.
Genetic testing for DM provides valuable information for breeders, veterinarians, and dog owners. Breeders can use test results to make informed breeding decisions that reduce the prevalence of the mutation while preserving healthy genetic diversity within the breed population. Avoiding the breeding of two carrier dogs significantly reduces the risk of producing at-risk offspring.
For dog owners, understanding a dog's DM status allows for proactive monitoring and early supportive care. Dogs identified as at risk may benefit from regular neurological evaluations, physical therapy, mobility support devices, and exercise management strategies designed to maintain quality of life. While there is currently no cure for Degenerative Myelopathy, supportive care can help affected dogs remain mobile and comfortable for as long as possible.
The Degenerative Myelopathy (DM) Health Test is a reliable genetic screening tool that supports responsible breeding practices, promotes canine neurological health, and helps reduce the impact of this inherited spinal cord disorder in future generations. Through early detection and informed breeding decisions, breeders and owners can contribute to healthier dogs and improved long-term welfare.
