Phenotype: In affected cats, uncoordinated eye movement is often observed, as well as owner-reported increased eye-shine (tapetal reflectivity) that occurs as thinning of the retina progresses. Onset of photoreceptor loss is around 5 weeks of age with severe loss by 16 weeks of age.
Mode of Inheritance: Autosomal recessive
Alleles: N = Normal, PRA = Progressive retinal atrophy (Persian derived)
Breeds appropriate for testing: Persian, British Longhair, British Shorthair, Himalayan, Exotic Longhair, Exotic Shorthair, Napoleon, and other Persian-derived breeds and crosses
Explanation of Results:
Cats with N/N genotype will not have Persian-derived progressive retinal atrophy. They cannot transmit this Persian-derived PRA variant to their offspring.
Cats with N/PRA genotype will not have Persian-derived progressive retinal atrophy, but are carriers. They will transmit this Persian-derived PRA variant to 50% of their offspring. Matings between two carriers are predicted to produce 25% kittens affected by Persian-derived progressive retinal atrophy.
Cats with PRA/PRA genotype will have Persian-derived progressive retinal atrophy, a condition leading to blindness.
At least 15 business days; may be delayed beyond 15 business days if sample requires additional testing, or a new sample is requested.
Cat DNA tests are carried out using cells collected from your cat's cheeks and gums using household cotton swabs.
The cat DNA submission form with instructions, pricing, and a place to tape the cotton swabs can be printed from your home computer after signing up for a MyVGL account and placing an order. Test kits are not mailed.
Purchase regular household cotton swabs for cat DNA collection (the cotton swabs can be purchased at a pharmacy or drug store)
Use both ends of the two cotton swabs for a total of four swabs.
Collect the DNA sample by swabbing the cheek and gums of the cat.
After swabbing the cheek and gums, tape the cotton swabs to the bar-coded submission form printed from your MyVGL account.
Persian cats have a demonstrated form of progressive retinal atrophy (PRA-pd). The disease is inherited in an autosomal recessive fashion with both sexes being equally affected. Onset of photoreceptor loss is around 5 weeks of age with severe loss by 16 weeks of age. In affected cats, uncoordinated eye movement is often observed, as well as owner-reported increased eye-shine (tapetal reflectivity) as thinning of the retina progresses. Corneal thinning is not observed. Cats with one normal and one mutated gene (carriers) have Retinal Pigment Epithelium changes but maintain normal vision without photoreceptor loss. Mating between two carrier cats is expected to produce 25% blind kittens.
Research by Dr. B. Gandolfi in the laboratory of Dr. Leslie Lyons, University of Missouri, identified the mutation associated with PRA-pd. Testing for this PRA-pd variant assists owners and breeders in identifying affected and carrier cats.