Other Names: GR-PRA2, GR2-PRA
Inheritance: Autosomal Recessive
Mutation(s): 1 bp deletion (del A)
Affected Gene(s): TTC8
Affected Breed(s): Australian Labradoodle, Golden Retriever, Goldendoodle, Labradoodle, Labrador Retriever

Common Symptoms

Progressive retinal atrophy, golden retriever 2 (GR-PRA2) is a late-onset inherited eye disease affecting dogs. Affected dogs begin showing clinical symptoms related to retinal degeneration between 4 to 5 years of age on average, though age of onset can vary. Initial clinical signs of progressive retinal atrophy involve changes in reflectivity and appearance of a structure behind the retina called the tapetum that can be observed on a veterinary eye exam. Progression of the disease leads to thinning of the retinal blood vessels, signifying decreased blood flow to the retina. Affected dogs initially have vision loss in dim light (night blindness) and loss of peripheral vision, progressing to complete blindness in most affected dogs.


  • 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. [PubMed: 24255994]