Stargardt Disease, Morbus Stargardt (STGD)

Stargardt disease is an autosomal recessive retinal degeneration affecting cone and rod photoreceptor cells. These are important for vision in bright and dim light. STGD was first identified in Labrador retriever dogs. Their visual function is impaired under daylight and dim light but still retain some vision throughout their lifetime. Pupils are dilated under daylight conditions. The function of rod photoreceptors is better preserved compared to cone photoreceptors. Additionally, reduction of number of photoreceptors is observed. On an eye exam affected dogs may also show attenuation of retina blood vessels. STGD occurs due to a genetic mutation that affects protein, which is responsible for normal function of retinal photoreceptors.

Inheritance: autosomal recessive

Mutation: ABCA4 gene

Genetic test: The method used for testing is extremely accurate and allows complete differentiation between affected animals, carriers and healthy dogs. Testing can be done at any age.