Breeds Affected: English Setter
Samples Accepted: Blood, Buccal Swabs
Disease Information: NCL8 is a lysosomal storage disease that is normally diagnosed around 1-2 years of age. A rapid disease progression of seizures, including difficulties walking and keeping balance, decreasing vision and cognitive problems lead to death at around 2 years of age.
Inheritance Information: NCL8 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/ncl8 The dog is a carrier, and can pass the allele on to approximately 50% of any offspring. If bred to another N/nlc8 carrier, approximately 25% of the offspring will be normal, 50% will be carriers, and 25% will be affected.
ncl8/ncl8 The dog is affected. If bred to a normal animal, 100% of the offspring will be carriers. If bred to an N/nlc8 carrier, 50% of the offspring will be carriers and 50% will be affected.
– Carriers may be bred to normal animals (N/ncl8 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/ncl8 x N/ncl8) is not recommended due to the possibility of 25% of the offspring being affected.
– Affected animals (ncl8/ncl8) should not be used for breeding.
Test Information: This mutation test identifies a single base change in the CLN8 gene.
Katz, ML., Khan, S., Awano, T., Shahid, SA., Siakotos, AN., Johnson, GS.: A mutation in the CLN8 gene in English Setter dogs with neuronal ceroid-lipofuscinosis. Biochem Biophys Res Commun 327:541-7, 2005. Pubmed reference: 15629147. Doi: 10.1016/j.bbrc.2004.12.038.
Further information is available at the Online Mendelian Inheritance in Animals website.