Testing for prcd-PRA progressive retinal atrophy in dogs

Prcd-PRA is one of the many different forms of progressive retinal atrophy that can affect dogs; a condition that ultimately, causes blindness in dogs that are affected. While the condition does not cause any pain to the affected dog, the blindness that it leads to cannot be treated or reversed, and so it does of course represent a significant impact in the affected dog’s quality of life.

There are a whole range of different types of canine progressive retinal atrophy that affect different parts of the eyes and how they function, all of which ultimately cause the dog to lose their vision. Because progressive retinal atrophy is a hereditary condition that is passed on from parent dogs to their offspring, potential breeding stock should be tested for the markers of the condition before they are bred, to ensure that the genes responsible for the condition are not reproduced in the gene pool, and so, cannot affect more dogs.

The British Veterinary Association and The Kennel Club run a testing scheme for the condition, aimed at the owners of dogs of certain breeds that are more predisposed to the problem than most.

Due to the fact that progressive retinal atrophy comes in so many different forms, each of which have their own genetic markers, a different test is needed for each variant-and in this article, we will look at the prcd-PRA form of the condition, how it affects dogs, and how it is tested for.

What is prcd-PRA progressive retinal atrophy?

The name prcd-PRA stands for “progressive rod-cone degeneration progressive retinal atrophy,” and refers to a type of progressive retinal atrophy that causes eventual blindness due to the degeneration of the eye’s rods and cones, as indicated by the name.

In prcd-PRA, dogs are usually born with ostensibly normal, healthy eyes and normal vision, but over time, the rod and cone cells at the back of the retina, which are responsible for receiving environmental light and transmitting information to the brain, die off and are not renewed, leading to blindness.

What sort of dogs are prone to developing prcd-PRA?

Because prcd-PRA is a hereditary condition, it is passed down in the breed line from parent dogs to their offspring, and is much more prevalent in certain breeds of dogs than others. Some of the breeds that are most commonly affected by the condition include the Labrador retriever, Labradoodle, Golden retriever, Poodle, and the Cocker spaniel.

The Labradoodle is of course a hybrid breed of dog rather than a recognised pedigree breed, but as with all hereditary conditions, hybrid and cross breeds that have ancestry of breeds prone to the condition will also be at risk.

You can find out if your own pedigree dog is considered to be at risk for the condition by checking out The Kennel Club’s breeding health information section-however, the database does not record information on the hereditary health and risk factors of non-pedigree dogs such as the Labradoodle.

How would I know if my dog was developing prcd-PRA progressive retinal atrophy?

If your dog is a breed that is known to be at risk of the condition, and even if they aren’t but have ancestors or close relatives with the condition, having them tested for prcd-PRA is the only way to know for sure if they are likely to develop the condition.

Progressive retinal atrophy causes a slow-onset blindness that may first become apparent as night blindness, and generally, the vision of dogs that will be affected by prcd-PRA will not begin their decline into blindness until they reach the age of three or even older.

How does the condition’s heredity work?

The prcd-PRA form of progressive retinal atrophy is an autosomal recessive condition, which means that in order to inherit prcd-PRA, the dog in question must inherit the gene for the condition from each of their parents in order for it to cause blindness.

If the dog inherits just one copy of the gene (from one parent but not the other) they will not be affected by progressive retinal atrophy themselves, but they will become a carrier for the condition and so, may pass it on to their own offspring.

What does the test involve?

Testing for prcd-PRA in adult dogs that might become breeding stock allows prospective breeders to make an informed decision on whether or not the pair of dogs they might be considering mating are good candidates for breeding with a view to producing a healthy litter.

In order to test for the condition, you will need to ask your vet to take a DNA sample from your dog by swabbing the inside of their cheek, and this sample is then sent off to one of the various laboratories that test for the markers of the condition in order to return a result.

You can find a complete list of all of the laboratories that offer the test in The Kennel Club’s database.