Progressive Retinal Atrophy (GTPBP2-PRA)
Canine progressive retinal atrophies (PRA) are a group of genetically diverse diseases that cause retinal degeneration and varying degrees of vision loss. While some PRA mutations are shared across multiple breeds, many are breed-specific or found in breeds with shared ancestry.
Typical signs found by ophthalmoscopic examination are widespread tapetal hyper-reflectivity and retinal vascular attenuation.
Genetic testing complements clinical eye examinations with the advantage of detecting known PRA mutations before breeding age or before clinical signs present.
A genetic variant in the GTPBP2 gene has been associated with progressive retinal atrophy (PRA) in Labrador Retrievers. In affected animals, this variant leads to retinal degeneration, resulting in a progressive loss of vision.
The dogs exhibit typical signs of visual impairment, such as a reduced response to visual stimuli - for example, they may no longer follow a thrown ball - as well as an increased reliance on their sense of smell to navigate their surroundings.
The age of onset of the first symptoms varies and typically ranges between 7 months and 1.5 years. As the disease progresses, a secondary cataract (lens opacity) may also develop
