UC Davis School of Veterinary Medicine Veterinary Genetics Laboratory
Progressive Retinal Atrophy-Persian Derived (PRA-pd)


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. The VGL offers a DNA test for PRA-pd to assist owners and breeders in identifying affected and carrier cats.

Genetic testing for PRA-pd is recommended for Persians, Himalayans and Exotic Shorthairs. Additional breeds with potential Persian ancestry may also be at risk.

Procedure for collecting a feline DNA sample

Allow 2-6 business days for results.

Results reported as:

Test Result Progressive Retinal Atrophy-Persian Derived (PRA-pd)

Normal - no copies of the PRA-pd mutation


Carrier - 1 copy of the PRA-pd mutation; vision appears normal


Affected - 2 copies of the PRA-pd mutation; cat will go blind


Rah H, Maggs DJ, Blankenship TN, Narfstom K, Lyons LA. 2005. Early-Onset, Autosomal Recessive, Progressive Retinal Atrophy in Persian Cats. Invest. Ophthalmol. Vis. Sci. 46:1742-1747.

Manuscript in preparation: Causative mutation identified by Dr. B. Gandolfi in the laboratory of Dr. Leslie Lyons.


Veterinary Genetics Laboratory, Tel 530-752-2211, Email VGL