Progressive Retinal Atrophy 5, PRA5

A dog with decreased vision may be reluctant to walk down stairs, enter a dark room, or go outside at night. They may bump into door frames or corners and have difficulty fetching toys. You may notice a characteristic eyeshine due to increased reflectivity of the tapetum, the layer of the eye that reflects light. The dog's discernible visual impairment will typically lag behind changes observed by a veterinarian and electroretinogram (ERG) abnormalities.

This form of PRA is typically diagnosed at around four years old.

PRA is diagnosed by examination of the back of the eye (the fundus). In the early stages, observing changes to the retina may be difficult. Still, as the disease progresses, a veterinarian will notice increased reflectivity and thinning of the retinal blood vessels. Changes affect both eyes equally, helping to distinguish PRA from other retinal diseases. A veterinary ophthalmologist can perform an ERG, which measures the electrical activity, and thus the function, of the retinas.

Currently, there is no widespread treatment for progressive retinal atrophy. However, gene therapy is an evolving field.

Talk to your vet about your dog’s PRA result so you can work together to plan their ongoing care and monitoring.

Schedule regular eye exams with your vet or a veterinary ophthalmologist to monitor for changes or complications such as cataracts.

If your dog’s vision changes, help them adjust by keeping furniture and routines consistent, using verbal cues, and keeping them on a leash in unfamiliar areas.

Products such as protective halos can also help dogs navigate safely if their vision declines.

This variant was first described in the Giant Schnauzer.

Penetrance: This variant is inherited in an autosomal recessive manner, meaning a dog requires two copies of the variant to show signs of PRA5.

Gene

NECAP1 Exon 6

Inheritance type

recessive

Clinical category

Ophthalmologic

Citations

1. Hitti et al 2019

• Giant Schnauzer
• Dachshund
• Dachshund
• Dachshund (Miniature)
• Keeshond
• German Spitz
• Pomeranian