Mucopolysaccharidosis IIIA (Dachshund Type)

General Information: Mucopolysaccharidosis IIIA (MPS IIIA) in Dachshunds is an inherited lysosomal storage disorder that significantly affects the nervous system. This condition is due to insufficient activity of the enzyme heparan N-sulfatase, which is essential for the breakdown of heparan sulfate, a critical component of body tissues. The inability to degrade heparan sulfate leads to its accumulation, particularly in nerve cells, causing progressive neurological damage. Affected dogs typically exhibit symptoms around three years of age, including loss of coordination (ataxia), reduced reflexes, head tremors, swaying, and abnormal eye movements. Although the disease progresses slowly, it primarily manifests as neurological deterioration with minimal joint and organ involvement, differentiating it from other forms of mucopolysaccharidoses in dogs. Most affected dogs experience a significant decline in quality of life, often leading to euthanasia within a few years of diagnosis.

How to Read Your Dog's Test Results for this Genetic Variant:

Two Variants Detected: Dog Likely Affected

One Variant Detected: Dog Unlikely Affected

No Variants Detected: No Effect

Gene / Testing Information: Genetic testing of the SGSH gene is crucial for identifying carriers of mucopolysaccharidosis IIIA (Dachshund Type). This disorder is inherited in an autosomal recessive manner, meaning that a dog must inherit two copies of the mutated gene, one from each parent, to develop the condition. Carrier dogs, which possess only one copy of the mutation, generally do not exhibit symptoms but can pass the defective gene to their offspring. When two carriers are bred, there is a 25% chance that each puppy will inherit the disease and a 50% chance that each will be a carrier of the SGSH gene mutation. Reliable genetic testing is vital for responsible breeding practices to avoid mating two carriers, thus minimizing the risk of producing affected puppies with this debilitating neurological disorder. By identifying carriers and making informed breeding decisions, breeders can help prevent the propagation of this disease in Dachshund populations. It is also important to note that while genetic testing for the SGSH mutation is an effective way to reduce the risk of MPS IIIA, other genetic or environmental factors may also contribute to similar neurological conditions, necessitating comprehensive genetic screening and careful management.