Progressive Retinal Atrophy, Late-Onset (Lapponian Herder Type)

General Information: Progressive Retinal Atrophy, Late-Onset (PRA) in Lapponian Herders typically manifests as night blindness initially, with affected dogs beginning to show signs around 9 years of age. The disease progresses from difficulty seeing in low light to a loss of peripheral vision and eventually leads to complete blindness. Veterinary eye exams may reveal early signs such as changes in the tapetum's reflectivity—a layer behind the retina—as well as thinning of the retinal blood vessels, indicative of reduced retinal blood flow. As the condition advances, affected dogs may become entirely blind, significantly impacting their quality of life.

How to Read Your Dog's Test Results for this Genetic Variant:

Two Variants Detected: Dog Likely Affected

One Variant Detected: Dog Unlikely Affected

No Variants Detected: No Effect

Gene / Testing Information: Genetic testing for the IFT122 gene helps identify carriers of Progressive Retinal Atrophy, Late-Onset (PRA) in Lapponian Herders. This disease is transmitted through an autosomal recessive pattern, meaning a dog needs two copies of the mutated gene—one from each parent—to exhibit symptoms of the disease. Dogs carrying one copy of the mutation do not typically show disease symptoms but can pass the mutation to their offspring. Breeding decisions should be informed by genetic testing to prevent mating between carriers, which results in a 25% chance of producing affected offspring with each pregnancy. Responsible breeding practices, including avoiding the mating of carriers, are essential to reduce the prevalence of this condition in the breed. Non-carriers do not pose any risk of passing on the disease, although it is important to note that other genes might also influence the presence of different types of Progressive Retinal Atrophy, so a clear IFT122 test does not entirely rule out PRA risks from other genetic causes.