Breeds Affected: Australian Shepherd
Samples Accepted: Blood, Buccal Swabs
Disease Information: NCL6 is a lysosomal storage disease which can be diagnosed around 18 months of age. Affected dogs show symptoms including vision loss quickly progressing to full blindness and distinct behaviour changes including hyperactivity, circling, anxiety and decreasing cognitive abilities. This disease cannot be treated.
Inheritance Information: NCL6 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/ncl6 The dog is a carrier, and can pass the allele on to approximately 50% of any offspring. If bred to another N/nlc6 carrier, approximately 25% of the offspring will be normal, 50% will be carriers, and 25% will be affected.
ncl6/ncl6 The dog is affected. If bred to a normal animal, 100% of the offspring will be carriers. If bred to an N/nlc6 carrier, 50% of the offspring will be carriers and 50% will be affected.
– Carriers may be bred to normal animals (N/ncl6 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/ncl6 x N/ncl6) is not recommended due to the possibility of 25% of the offspring being affected.
– Affected animals (ncl6/ncl6) should not be used for breeding.
Test Information: This mutation test identifies a single base change in exon 7 of the CLN6 gene.
Katz, ML., Farias, FH., Sanders, DN., Zeng, R., Khan, S., Johnson, GS., O’Brien, DP.: A missense mutation in canine CLN6 in an Australian shepherd with neuronal ceroid lipofuscinosis. J Biomed Biotechnol 2011:198042, 2011. Pubmed reference: 21234413. Doi: 10.1155/2011/198042.
Further information is available at the Online Mendelian Inheritance in Animals website.