Factor VII Deficiency

Factor VII blood clotting defect or factor VII deficiency is a pathology, usually mild, that affects the blood clotting ability of several canine breeds and increases the risk of excessive bleeding after injury or surgery.

Symptoms

Dogs affected by factor VII deficiency may bruise easily, have frequent nosebleeds and prolonged bleeding after surgery or trauma.

Disease Management

If you observe symptoms related to the disease it is important that you go to your veterinarian for advice on how to manage the disease. It is important that the veterinarian is informed if your dog has this condition, especially before any surgical intervention.

Genetic basis

This disease follows an autosomal recessive mode of inheritance. Autosomal recessive inheritance means that the dog, regardless of sex, must receive two copies of the mutation or pathogenic variant to be at risk of developing the disease. Both parents of an affected dog must carry at least one copy of the mutation. Animals with only one copy of the mutation are not at increased risk of developing the disease, but may pass the mutation on to future generations. Breeding between dogs carrying genetic variants that can cause disease, even if they do not show symptoms, is not recommended.

Technical report

Factor VII is an essential protein encoded by the F7 gene necessary for normal blood clotting. Factor VII is found in the blood and when activated is involved in initiating the clotting process. Deficiency of this factor usually results in a mild bleeding disorder. The c.407G>A variant of F7 was the first to be identified in Beagle dogs with factor VII deficiency and is the one studied here. It has been shown to affect some 24 breeds and mongrels.

Most affected breeds

Alaskan Klee Kai
Beagle
Scottish Deerhound

Bibliography

Callan MB, Aljamali MN, Margaritis P,et al. A novel missense mutation responsible for factor VII deficiency in research Beagle colonies. J Thromb Haemost. 2006 Dec;4(12):2616-22.

Clark JA, Hooser SB, Dreger DL,et al. Investigation of a common canine factor VII deficiency variant in dogs with unexplained bleeding on autopsy. J Vet Diagn Invest. 2022 Sep;34(5):806-812.