Canine Fucosidosis (CF) is an autosomal recessive disorder found in English Springer Spaniels that affects the dog's ability to produce the enzyme alpha-fucosidase. Autosomal recessive disorders are disorders that can be passed from either parent and require two copies of the gene to show symptoms. This enzyme deficiency prohibits the normal breakdown and metabolism of complex sugars from within the cells. Instead, these compounds build up in the cells and eventually diminish the cell's ability to function properly. Accumulation of these sugars in the brain and nervous systems gives rise to the outward signs of the disease.
The disorder affects dogs between 18 months and 4 years of age. Clinically, the disease is characterized by a decrease in central nervous system (CNS) functions. This means that the brain is affected. Signs can include:
- loss of learned behavior
- change in temperament
- loss of balance
- weight loss
From the onset of symptoms, the disease will progress quickly and is fatal.
Because CF is a recessive disorder, a dog must have two copies of the mutation in order for the disease to manifest. This means that a dog can have one copy of the mutation and not experience any signs or symptoms of CF. This dog would be known as a carrier. The carrier can then pass on either the normal gene or the mutated gene to any offspring. If two carriers are bred, there is a 25% per puppy that they will develop symptoms of CF.
|Affected: Dog has two copies of the Fucosidosis mutation and may be affected by the disorder. The gene will always be passed to every offspring.
|Carrier: Dog has one copy of the Fucosidosis mutation. The dog is not affected by Fc but may pass the gene to offspring.
|Clear: Dog is negative for the mutation associated with Fucosidosis.
Occhiodoro T, Anson DS. Isolation of the canine alpha-L-fucosidase cDNA and definition of the fucosidosis mutation in English Springer Spaniels. Mamm Genome. 1996 Apr; 7(4):271-4. [PubMed: 8661697]
Skelly BJ, Sargan DR, Herrtage ME, Winchester BG. The molecular defect underlying canine fucosidosis. J Med Genet. 1996 Apr; 33(4):284-8. [PubMed: 8730282]