Progressive Retinal Atrophy (rcd3-PRA)
The term "PRA" refers to 'Progressive Retinal Atrophy," which is a group of disorders in which cells in the retina of the eye degenerate, eventually leading to a lack of vision. One form of PRA occurs in Cardigan Welsh Corgis, known as rcd3-PRA. In this form of PRA, the rod cells of a young Corgi begin to die, often before the age of 1 year old. The rod cells are responsible for vision in low-light or night settings, so the dog is quickly night-blind. At 2-3 years old, the dog's cone cells also degenerate and die off. This leads to a loss of colour vision as well, resulting in complete blindness. Unfortunately, there is no cure for PRA.
Because rcd3-PRA is a recessive disorder, a dog can be an obligate carrier and not display any symptoms of the disease. This makes DNA testing an important tool to ensure the health of all puppies. Breeding two carrier dogs can result in affected offspring. There is a 25% chance that a pup could receive the mutated allele from each parent and be affected by the disease.
Animal Genetics accepts buccal swab, blood, and dewclaw samples for testing. Sample collection kits are available and can be ordered at test now.
Test Is Relevant to the Following Breeds:
- Cardigan Welsh Corgi
Animal Genetics UK offers DNA testing for Progressive Retinal Atrophy (rcd3-PRA). The genetic test verifies the presence of the recessive PRA Gene and presents results as one of the following:
|PRA3/PRA3||Affected||The dog carries two copies of the mutant gene and is homozygous for rcd3-PRA. The dog will display symptoms associated with the disorder and will always pass a copy of the mutation to its offspring.|
|PRA3/n||Carrier||Both the normal and mutant copies of the gene detected. The dog is a carrier for rcd3-PRA and could pass on either allele to any offspring.|
|n/n||Clear||Dog tested negative for the rcd3-PRA gene mutation and will not pass on the defective gene to its offspring.|