GM1 Gangliosidosis (Portuguese Water Dog Type)

General Information: GM1 Gangliosidosis (GM1) (Portuguese Water Dog Type) is a genetic lysosomal storage disorder that severely impacts dogs, particularly the brain and nervous system. This condition arises from insufficient activity of the enzyme beta-galactosidase, which is crucial for breaking down specific carbohydrates within cells. The enzyme deficiency causes an accumulation of GM1 and other breakdown products in cells, leading to cellular damage. Affected dogs typically exhibit symptoms between 2 to 6 months of age, including vision loss, nystagmus (rapid eye movement), difficulty walking, loss of balance, head tremors, abnormal bone growth, and weight loss. Once symptoms appear, the disease progresses rapidly, usually resulting in death by one year of age.

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 for GM1 Gangliosidosis (GM1) (Portuguese Water Dog Type) involves screening for mutations in the GLB1 gene to determine carrier status. This disorder is inherited in an autosomal recessive manner, meaning a dog must inherit two copies of the mutated gene, one from each parent, to develop the disease. Carriers do not typically exhibit symptoms but can pass the mutation to their offspring. When two carriers are bred, each puppy has a 25% chance of being affected and a 50% chance of being a carrier. To prevent producing affected puppies and eliminate the mutation from breeding lines, it is crucial to avoid breeding two carriers. Genetic testing is essential for responsible breeding practices, ensuring that dogs that are not carriers of the mutation do not pose a risk of producing affected puppies.