Coagulation Factor VII Deficiency is an inherited bleeding disorder affecting Airedale terriers. Factor VII is an essential protein needed for normal blood clotting. Deficiency of this factor most commonly results in a mild bleeding disorder. An affected dog may bruise easily, have frequent nosebleeds, and exhibit prolonged bleeding after surgery or trauma. In rare cases, the bleeding may be severe. Due to the mild nature of this disorder, affected dogs may not be identified until a surgery is performed or trauma occurs at which time excessive bleeding is noted. Veterinarians performing surgery on dogs that are known to have coagulation factor VII deficiency should have ready access to blood banked for transfusions. Most dogs with this condition will have a normal lifespan despite increased blood clotting times.
Breed-Specific Information for the Airedale Terrier
The Mutation of the F7 gene associated with coagulation factor VII deficiency has been identified in Airedale terriers, although its overall frequency in this breed is unknown.
Genetic testing of the F7 gene in Airedale terriers will reliably determine whether a dog is a genetic Carrier of coagulation factor VII deficiency. Coagulation Factor VII Deficiency is inherited in an Autosomal Recessive manner in dogs meaning that they must receive two copies of the mutated gene (one from each parent) to develop the disease. In general, carrier dogs do not have features of the disease but when bred with another carrier of the same Mutation, there is a risk of having affected pups. Each pup that is born to this pairing has a 25% chance of inheriting the disease and a 50% chance of inheriting one copy and being a carrier of the F7 gene mutation. Reliable genetic testing is important for determining breeding practices. In order to eliminate this mutation from breeding lines and to avoid the potential of producing affected pups, breeding of known carriers to each other is not recommended. Airedale terriers that are not carriers of the mutation have no increased risk of having affected pups.
There may be other causes of this condition in dogs and a normal result does not exclude a different mutation in this gene or any other gene that may result in a similar genetic disease or trait.
Callan MB, Aljamali MN, Griot-Wenkl ME, Pollak ES, Werner P, Giger U, High KA. Molecular characterization of hereditary factor VII deficiency in the beagle. J Vet Intern Med. 2005; 19: 448-449 (abstract) [not in PubMed]
Callan MB, Aljamali MN, Margaritis P, Griot-Wenk ME, Pollak ES, Werner P, Giger U, High KA. A novel missense mutation responsible for factor VII deficiency in research Beagle colonies. J Thromb Haemost. 2006 Dec; 4(12):2616-22.
Carlstrom LP, Jens JK, Dobyns ME, Passage M, Dickson PI, Ellinwood NM. Inadvertent propagation of factor VII deficiency in a canine mucopolysaccharidosis type I research breeding colony. Comp Med. 2009 Aug;59(4):378-82.
Donner J, Kaukonen M, Anderson H, Moller F, Kyostila K, Sankari S, Hytonen M, Giger U, Lohi H. Genetic Panel Screening of Nearly 100 Mutations Reveals New Insights into the Breed Distribution of Risk Variants for Canine
Hereditary Disorders. PLoS One. 2016 Aug 15;11(8):e0161005.
Kaae JA, Callan MB, Brooks MB. Hereditary factor VII deficiency in the Alaskan Klee Kai dog. J Vet Intern Med. 2007 Sep-Oct;21(5):976-81.
Withnall E, Giger U. Effects of recombinant human activated factor VII and canine fresh frozen plasma in Beagles with hereditary coagulation factor VII deficiency. J Vet Intern Med. 2006; 20: 766 (abstract) [not in PubMed]