Breeds Affected: Cairn Terrier, West Highland White Terrier
Samples Accepted: Blood, Buccal Swabs
Disease Information: Globoid Cell Leukodystrophy, also known as Krabbe Disease, is a lysosomal storage disease that causes progressive neurological disorders: problems walking, tremors, weakness, and eventually blindness and paralysis. Symptoms are first seen before 6 months of age, and affected dogs are usually humanely euthanized as the disease progresses.
Inheritance Information: Globoid Cell Leukodystrophy 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/gcl The dog is a carrier, and can pass the allele on to approximately 50% of any offspring. If bred to another N/gcl carrier, approximately 25% of the offspring will be normal, 50% will be carriers, and 25% will be affected.
gcl/gcl The dog is affected, and if bred to a normal animal, 100% of the offspring will be carriers. If bred to an N/gcl carrier, 50% of the offspring will be carriers and 50% will be affected.
– Carriers may be bred to normal animals (N/gcl 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/gcl x N/gcl) is not recommended due to the possibility of 25% of the offspring being affected.
– Affected animals (gcl/gcl) should not be used for breeding.
Test Information: This test identifies a single base change in the GALC gene.
Wenger, D.A., Victoria, T., Rafi, M.A., Luzi, P., Vanier, M.T., Vite, C., Patterson, D.F., Haskins, M.H.: Globoid cell leukodystrophy in cairn and West Highland white terriers. Journal of Heredity 90:138-142, 1999. Pubmed reference: 9987921
Further information is available at the Online Mendelian Inheritance in Animals website.