BUMBLE BEE BELLA MARE inherited one copy of the variant we tested for Stargardt Disease
This variant should not impact SUTTON’s health. This variant is inherited in an autosomal recessive manner, meaning that a dog needs two copies of the variant to show signs of this condition. SUTTON is unlikely to develop this condition due to this variant because she only has one copy of the variant.
Your dog carries this variant and will pass it on to ~50% of her offspring. You can email breeders@embarkvet.com to discuss with a genetic counselor how the genotype results should be applied to a breeding program.
Stargardt Disease is a non-painful inherited degenerative disorder of the rod and cone photoreceptor cells of the retina that results in vision loss. Rods affect vision in the dark, or low light, and cones affect vision in light. As the disease progresses, cone function is profoundly abnormal, whereas rod function is better preserved. Vision slowly deteriorates, but some vision seems to remain throughout an affected dog’s lifetime.
Although subtle changes to vision and the retinas may be noted at 1-2 years of age, dogs may not be diagnosed until middle or advanced age when changes are more noticeable.
Stargardt Disease is diagnosed by examining the fundus, or back of the eye. It may be difficult to observe any obvious changes to the retina. But as the disease progresses, there will be mottling of the tapetum (a layer of tissue immediately behind the retina) and thinning of the retinal blood vessels. Changes to the back of the eye are bilateral and symmetrical, helping to distinguish Stargardt Disease from other retinal diseases. If the retinas cannot be evaluated due to other abnormalities, a veterinary ophthalmologist can perform electroretinography (ERG), the definitive test, which measures the electrical activity and, thus, the function of the retinas.
Currently, there is no widespread treatment for Stargardt Disease; however, gene and stem cell therapies are an evolving field.
- Affected dogs may experience a painful sensitivity to light and may squint in bright light.
- Dog owners can help affected dogs navigate their homes and the outside world by keeping furniture in the same location, ensuring they are on a leash in unfamiliar territory, and training them to understand verbal commands or using scent markers.