Progressive Retinal Atrophy, Golden Retriever 1
Affected Genes: SLC4A3
Inheritance: Autosomal Recessive
Variant(canFam6):
chr37:26971203: A>AC
Breed: Golden Retriever
Goldendoodle
Lab/Golden Cross
Lhasa Apso
Service/Assistance Golden Retriever
Service/Assistance Lab/Golden Retriever cross
General Information: Progressive Retinal Atrophy, Golden Retriever 1 (GR-PRA1), is a genetic eye disease that affects various dog breeds, including Golden Retrievers, Goldendoodles, Lhasa Apsos, and Labrador/Golden Retriever crosses. This condition is characterized by the gradual degeneration of the retina, leading to progressive vision loss. Dogs with GR-PRA1 generally begin to show clinical symptoms between the ages of 6 to 7 years, though the exact age of onset can vary. Early signs include changes in the appearance and reflectivity of the tapetum, a structure located behind the retina, which can be detected during a veterinary eye exam. As the disease progresses, retinal blood vessels thin due to decreased blood flow, initially causing night blindness and loss of peripheral vision. Eventually, most affected dogs experience complete blindness. Despite the severity of vision impairment, GR-PRA1 does not typically cause pain, but it significantly affects the quality of life as the dog ages.
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 the SLC4A3 gene is crucial for identifying carriers of the mutation responsible for Progressive Retinal Atrophy, Golden Retriever 1 (GR-PRA1). This condition 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. Dogs carrying only one copy of the mutation (carriers) do not exhibit symptoms but can pass the mutation to their offspring. When two carriers are bred, each puppy has a 25% chance of developing GR-PRA1 and a 50% chance of being a carrier. Reliable genetic testing is essential for responsible breeding practices to avoid mating two carriers, thereby reducing the risk of producing puppies affected by this condition. By identifying carriers and making informed breeding decisions, breeders can help eliminate this debilitating eye disease from the dog population, promoting healthier and more resilient future generations. It is important to note that while genetic testing for the SLC4A3 mutation reduces the risk of GR-PRA1, other forms of progressive retinal atrophy caused by mutations in different genes may still be present, necessitating comprehensive genetic screening and careful management.
References:
Downs LM, Wallin-Hakansson B, Boursnell M, Marklund S, Hedhammar A, Truve K, Hubinette L, Lindblad-Toh K, Bergstrom T, Mellersh CS. A frameshift mutation in golden retriever dogs with progressive retinal atrophy endorses SLC4A3 as a candidate gene for human retinal degenerations. PLoS One 2011 6(6):e21452.