Breeds Affected: Irish Terrier, Kromfohrländer
Samples Accepted: Blood, Buccal Swabs
Disease Information: HFH causes a thickening of the foot pad surface in affected dogs, first noticeable at 4-5 months of age. Cracks that develop in the pads can lead to lameness.
Inheritance Information: Hereditary Footpad Hyperkeratosis 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/hfhThe dog is a carrier, and can pass the allele on to approximately 50% of any offspring. If bred to another N/hfh carrier, approximately 25% of the offspring will be normal, 50% will be carriers, and 25% will be affected.
hfh/hfh The dog is affected, and if bred to a normal animal, 100% of the offspring will be carriers. If bred to an N/hfh carrier, 50% of the offspring will be carriers and 50% will be affected.
– Carriers may be bred to normal animals (N/hfh 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/hfh x N/hfh) is not recommended due to the probability of 25% of the offspring being affected.
– Affected animals (hfh/hfh) should not be used for breeding.
Test Information: This test identifies a single base change in the gene FAM83G.
Drögemüller, M., Jagannathan, V., Becker, D., Drögemüller, C., Schelling, C., Plassais, J., Kaerle, C., Dufaure de Citres, C., Thomas, A., Müller, E.J., Welle, M.M., Roosje, P., Leeb, T.: A mutation in the FAM83G gene in dogs with hereditary footpad hyperkeratosis (HFH). PLoS Genet 10:e1004370, 2014. Pubmed reference: 24832243. DOI: 10.1371/journal.pgen.1004370
Further information is available at the Online Mendelian Inheritance in Animals website.