Stargardt Disease

Find out if your Labrador retriever could develop Stargardt Disease at CAGT.

UK only
CODE STG-ABCA4
Categories ,
Breed(s)
OMIA OMIA002179-9615
Aliases

Results from this test will be reported as detailed in the Registry Reporting list.

Overview

Stargart disease is an inherited eye disease that affects dogs, primarily Labrador Retrievers. Onset of significant clinical signs is late in life, with affected dogs presenting with observable visual problems around 10 years of age. As with other retinal degenerations, such as progressive retinal atrophy, Stargardt disease is characterised by the degeneration of the rod and cone photoreceptor cells of the retina. Dog therefore experience visual deficits in bright and low light conditions. It is a progressive disease and symptoms will get worse as the dog ages.

Autosomal Recessive

The frameshift insertion in the gene called ABCA4 that causes Stargardt Disease in Labrador retriever is autosomal recessive. This means that dogs that carry two copies of the mutation (homozygotes) will almost certainly develop Stargardt Disease during their lives. Dogs that carry a single copy of the mutation (also known as carriers or heterozygotes) will not develop Stargardt Disease as a result of the ABCA4 mutation, but they will pass the mutation onto about half of any offspring they have. Breeding dogs that will not develop Stargardt Disease should be the breeder’s priority, with a reduction in mutation frequency within the whole breed being the secondary, longer-term target.

Carriers can be bred from safely, provided they are mated to a dog that has also been tested and is clear of the ABCA4 mutation (i.e. carry no copies of the mutation). If a carrier is mated to a clear dog approximately half of the resulting puppies will also be carriers, so should be tested themselves prior to breeding. Breeding carriers to tested, clear dogs is safe, in terms of avoiding dogs affected with Stargardt Disease, and will help to maintain the genetic diversity of a breed. It is therefore encouraged, particularly in the first few generations following the availability of a new genetic test, so that other desirable characteristics and traits can be preserved before the frequency of the disease mutation within the breed is gradually reduced.

Gene ABCA4
Variant c.4176insC, p.F1393Lfs*1395
Assay Type Variant Specific
Inheritance Autosomal Recessive
Severity Low-Moderate: Affected animals experience discomfort or dysfunction of some kind, but life expectancy is not affected.
Publication

Mäkeläinen S, M Gòdia, M Hellsand et al. (2019) An ABCA4 loss-of-function mutation causes a canine form of Stargardt disease. PLOS Genetics. 15(3): e1007873 . DOI: 10.1371/journal.pgen.1007873.