Progressive Retinal Atrophy (Golden Retriever Type2)
Turnaround: 3-5 business daysTurnaround: 7-10 business days
Price: $45.00Price: £40.00
Breeds: Double Doodle, Goldadoodlier, Goldador, Goldador Doodle, Goldalier, Golden Retriever, Goldendoodle, Miniature Goldendoodle, Mixed Breed, Unspecified
Description
Progressive Retinal Atrophy (PRA) is a category of genetic mutations that cause vision loss and blindness. Photoreceptor cells (light-sensing cells) in the retina begin to degenerate, typically progressing from a loss of night vision to complete blindness.
PRA affects many different dog breeds, and these mutations are breed-specific. In Golden Retrievers, two mutations have been identified (in addition to prcd-PRA) known as GR-PRA1 and GR-PRA2.
Both GR-PRA1 and GR-PRA2 are inherited autosomal recessive disorders. Autosomal recessive disorders are disorders that can be passed from either parent and require two copies of the gene to show symptoms. Because both GR-PRA1 and GR-PRA2 are recessive disorders, a dog must have two copies of the mutation in order for the disease to manifest. This means that a dog can have one copy of the mutation and not experience any signs or symptoms of GR-PRA1 or GR-PRA2. This dog would be known as a carrier. The carrier can then pass on either the normal gene or the mutated gene to any offspring. If two carriers are bred, there is a 25% per puppy that they will develop symptoms of GR-PRA1 or GR-PRA2.
Possible Results
| Genotype | Description |
|---|---|
| P/P | Affected: Dog has two copies of the GR-PRA2 mutation and will be affected. The mutation will be passed to every offspring. |
| n/P | Carrier: Dog has one copy of the GR-PRA2 mutation. The dog is not affected by GR-PRA2 but may pass the mutation to offspring. |
| n/n | Clear: Dog is negative for the mutation associated with GR-PRA2. |
Reference
Downs LM, Hitti R, Pregnolato S, Mellersh CS. Genetic screening for PRA-associated mutations in multiple dog breeds shows that PRA is heterogeneous within and between breeds. Vet Ophthalmol. 2014 Mar;17(2):126-30. doi: 10.1111/vop.12122. Epub 2013 Nov 21. [PubMed: 24255994]