Progressive Retinal Atrophy, Early-Onset (Portuguese Water Dog Type)

General Information: Progressive Retinal Atrophy, Early-Onset (Portuguese Water Dog Type) is a hereditary eye disorder that primarily affects Portuguese Water Dogs, leading to vision problems at a young age, typically between 2 to 3 years. The disease manifests with initial changes in the tapetum, a reflective layer behind the retina, observable during veterinary eye exams. As the condition progresses, there is a noticeable thinning of the retinal blood vessels, indicating reduced blood flow and nourishment to the retina. Affected dogs often experience night blindness and a gradual loss of peripheral vision, which can ultimately lead to complete blindness. Early detection is crucial, as it helps manage the condition and improve the quality of life for affected dogs.

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 Progressive Retinal Atrophy, Early-Onset (Portuguese Water Dog Type) focuses on detecting mutations in the CCDC66 gene. This disease follows an autosomal recessive inheritance pattern, meaning a dog must inherit two copies of the mutated gene (one from each parent) to exhibit the condition. Carrier dogs, which possess only one copy of the mutation, typically do not show symptoms but can pass the mutation to their offspring. When two carriers are bred, there is a 25% chance of producing affected puppies and a 50% chance of producing carriers. Genetic testing is essential for responsible breeding practices, allowing breeders to identify carriers and avoid breeding pairs that could produce affected pups. By ensuring that at least one parent does not carry the mutation, the risk of passing on the disease can be significantly reduced, thus helping to eradicate the condition from breeding lines and promoting the health of future generations.