Progressive retinal atrophy (PRA) is a leading hereditary cause of blindness in pedigree dogs as is its counterpart retinitis pigmentosa (RP) in humans. PRA shows genetic heterogeneity, as does RP, with several distinct forms already recognized and several more remaining to be investigated.
The retina is a thin layer of neural cells that lines the back of the eyeball. The vertebrate retina contains photoreceptor cells (rods and cones) that respond to light. The cones mediate high-resolution vision and colour vision. The rods mediate lower-resolution, black-and-white, night vision. The degeneration of the retina results in loss of vision, often leading to blindness. One can distinguish between late onset forms of PRA and early onset (whelp-age) dysplastic changes. The clinical and ophthalmologic signs of both forms are similar.
Affected dogs suffer from bilateral Mydriasis, the reflection of the Tapetum lucidum is increased and the retinal vascular network appears atrophic. Currently, there is no treatment for the disease.
Golden Retriever:
Three different mutations causing PRA have been identified in the Golden Retrievers breed: the well-known prcd-PRA , the GR_PRA1 mutation and
GR_PRA2 which were recently identified by researchers of the Animal Health Trust and the university of Uppsala.
LABOKLIN offers DNA testing for all three mutations individually in addition to a special discounted offer for the combined testing of the three mutation. Details of the special offer can be found on this link: Golden Retriever PRA Special offer.