Autosomal Dominant Progressive Retinal Atrophy

PRA is a subtle disease and dogs adapt very well to the slow loss of vision. However, with this form of PRA, high intensity light can trigger a rapid decline in vision over 2-4 weeks. You may notice that your dog is reluctant to go down the stairs, bumps into door frames or corners, or takes a longer time to fetch a toy.

Symptoms appear as early as 8 weeks of age, but often are not noticed until a dog is 2-3 years of age.

Veterinarians use a focused light to examine the pupils. In affected dogs, the pupils will appear more dilated and slower to contract. Your vet may also use a lens to visualize the retina at the back of the eye to look for changes in the optic nerve or blood vessels. You may be referred to a veterinary ophthalmologist for a definitive diagnosis.

Currently, there is no definitive treatment for PRA. Supplements, including antioxidants, have been proposed for management of the disease, but have not been scientifically proven effective.

Talk to your vet about your dog’s AD-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.

Protect your dog’s eyes by avoiding prolonged exposure to bright or high-intensity light. Dog goggles designed to reduce glare can also help keep them comfortable outdoors.

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 mutation was first described in the English Mastiff and Bullmastiff.

Penetrance: This mutation is inherited in an autosomal dominant manner, meaning that one or two copies of this gene will cause the disorder.

Gene

RHO (Exon 1)

Inheritance type

dominant

Clinical category

Ophthalmologic

Citations

1. Cideciyan et al 2005
2. Kijas et al 2002

• Bullmastiff
• Mastiff