Breeds Affected: English Springer Spaniel
Samples Accepted: Blood, Buccal Swabs
Disease Information:Alpha Fucosidosis is a lysosomal storage disease that causes neurological disorders: problems walking, temperament change, the loss of learned behaviours, blindness, and eventually muscle wasting. Affected dogs usually die or are humanely euthanized by 4 years of age.
Inheritance Information: Alpha Fucosidosis is autosomal recessive, meaning that animals with two copies of this allele will be affected. Animals with one copy of the gene will be clinically-normal carriers.
The possible genotypes are:
N/N The dog is normal, and cannot produce affected offspring.
N/af The dog is a carrier, and can pass the allele on to approximately 50% of any offspring. If bred to another N/af carrier, approximately 25% of the offspring will be normal, 50% will be carriers, and 25% will be affected.
af/af The dog is affected, and if bred to a normal animal, 100% of the offspring will be carriers. If bred to an N/af carrier, 50% of the offspring will be carriers and 50% will be affected.
Recommendations:
– Carriers may be bred to normal animals (N/af x N/N) without any risk of producing affected offspring. The offspring should be tested before breeding to determine if they are carriers or normal.
– Breeding two carriers (N/af x N/af) is not recommended due to the possibility of 25% of the offspring being affected.
– Affected animals (af/af) should not be used for breeding.
Test Information: This test identifies a 14 base deletion in exon 1 of the FUCA1 gene.
Skelly, B.J., Sargan, D.R., Herrtage, M.E., Winchester, B.G.: The molecular defect underlying canine fucosidosis. Journal of Medical Genetics 33:284-288, 1996. Pubmed reference: 8730282
Further information is available at the Online Mendelian Inheritance in Animals website.