Factor VII Deficiency in Dogs: Causes, Breeds & Testing

Factor VII deficiency (FVIID) in dogs is an inherited disorder affecting the blood's ability to clot properly. This condition results from a shortage or dysfunction of Factor VII, a protein essential for the clotting cascade that prevents excessive bleeding after injury. FVIID is an autosomal recessive genetic condition, meaning a dog must inherit two copies of the defective gene to be affected, while carriers carry the gene without symptoms but can pass it to offspring.

Understanding this condition is important for dog owners, breeders, and vets alike, especially in affected breeds where screening can help manage and prevent the disorder's propagation. This article explores Factor VII deficiency in dogs, the breeds at risk, how the heredity works, testing procedures, and management strategies to help you care responsibly for your pet or breeding dogs.

What is Factor VII Deficiency?

Factor VII is a vitamin K-dependent glycoprotein produced in the liver that plays a vital role in the extrinsic pathway of blood coagulation. When a blood vessel is injured, Factor VII activates a cascade of clotting factors that ultimately form a clot to stop bleeding.

Dogs affected by FVIID have lower than normal levels or dysfunctional Factor VII, leading to impaired clotting. Clinically, this can range from mild cases—where minor injuries take longer to stop bleeding—to severe cases with significant, potentially life-threatening bleeding episodes often triggered by trauma or surgery.

As Factor VII deficiency affects clotting, the condition can be detected by blood clotting tests, especially prothrombin time (PT) prolongation while activated partial thromboplastin time (aPTT) remains normal. However, genetic testing remains the definitive method for diagnosis and carrier identification, crucial for breeders.

Which Dog Breeds Are Affected?

Factor VII deficiency has been identified in multiple breeds worldwide. In the UK, the breeds known to carry the gene mutation at a significant frequency include the Beagle puppies, the Alaskan Klee Kai, and the Scottish Deerhound. The Beagle addition is relatively recent, with the UK Kennel Club recommending testing since 2015.

Mixed breed dogs with ancestry from any of these breeds can also inherit the condition. Knowing your dog's lineage can help assess risk, especially if you plan to breed your dog responsibly.

How Is Factor VII Deficiency Inherited?

This condition is inherited in an autosomal recessive manner. Each dog inherits one gene from each parent which determines their status:

• Clear: No mutation; will neither suffer from nor pass on the condition.
• Carrier: One copy of the mutation; typically asymptomatic but can pass the gene on.
• Affected: Two copies of the mutation; shows clinical signs and can pass the condition.

The combination of parental statuses affects the likelihood of affected or carrier puppies:

• Two clear parents: all puppies clear.
• Two affected parents: all puppies affected.
• Two carriers: about 25% affected, 50% carriers, 25% clear.
• Clear x Carrier: 50% clear, 50% carriers.
• Clear x Affected: all puppies carriers.
• Carrier x Affected: 50% carriers, 50% affected.

These genetic principles highlight the importance of responsible breeding and testing to avoid producing affected puppies.

How To Test Your Dog for Factor VII Deficiency

A simple DNA test performed by an approved laboratory under The Kennel Club's testing scheme can determine your dog's status. Typically, a cheek swab or blood sample is submitted, and the results classify the dog as clear, carrier or affected.

Genetic testing helps breeders make informed decisions to prevent affected litters while maintaining breed health. It is recommended for at-risk breeds and any dog intended for breeding.

Clinical Signs and Management

Signs of Factor VII deficiency vary but often include prolonged bleeding from minor injuries, bruising, nosebleeds, gum bleeding in puppies, or excessive bleeding post-surgery. Some dogs may not show symptoms until challenged by injury or surgery.

Management focuses on avoiding trauma, careful surgical planning, and having veterinary interventions like blood transfusions ready if needed. Life expectancy can be normal with appropriate precautions.

Early diagnosis and breeding management can reduce the incidence and improve welfare for future generations.

Why Responsible Breeding Matters

Factor VII deficiency underscores why genetic testing and responsible breeding practices are vital in the dog community. Using only clear or carefully paired carrier dogs for breeding reduces the risk of affected puppies and improves the overall breed health.

The Kennel Club and British Veterinary Association provide updated guidance and testing schemes, helping breeders and owners ensure puppies are born healthy and minimise inherited disease risks.

As a prospective dog owner or breeder, seeking puppies from reputable breeders who perform these tests contributes to a healthier dog population.

Conclusion

Factor VII deficiency is a hereditary bleeding disorder affecting certain dog breeds, particularly Beagles, Alaskan Klee Kai, and Scottish Deerhounds in the UK. Understanding the genetic inheritance, clinical signs, testing, and management helps owners and breeders act responsibly.

Genetic testing is a critical tool in preventing the spread of this condition in breeding lines, ensuring dogs live healthier lives with fewer bleeding complications.

If you own an at-risk breed or are considering breeding, consult your vet or The Kennel Club for testing advice and join responsible breeding efforts to protect future generations.