Hemophilia B (Cairn Terrier Type)

General Information: Hemophilia B (Cairn Terrier Type) is a genetic bleeding disorder resulting from a deficiency in coagulation factor IX, an essential protein required for normal blood clotting. The severity of the bleeding tendency can vary between breeds. Severely affected dogs bruise easily, develop blood-filled masses (hematomas) under the skin and within muscles from mild trauma, and may experience internal bleeding, leading to bloody or dark tarry feces. Affected dogs may also show signs of lameness or stiffness if bleeding occurs in the joints. Mildly affected dogs may exhibit easy and excessive bruising and frequent nosebleeds. There is a significant risk of prolonged bleeding after surgery or trauma, which can sometimes be severe enough to cause death. Veterinarians performing surgery on affected dogs should have access to banked blood for transfusions. Despite the increased blood clotting times, most dogs with Hemophilia B can have a normal lifespan with appropriate management.

How to Read Your Dog's Test Results for this Genetic Variant:

Two Variants Detected: Dog Likely Affected

One Variant Detected: Dog Unlikely Affected

No Variants Detected: No Effect

Gene / Testing Information: Genetic testing for Hemophilia B (Cairn Terrier Type) involves screening for mutations in the F9 gene to determine carrier status. This disorder is inherited in an X-linked recessive manner, meaning female dogs must inherit two copies of the mutated gene (one from each parent) to develop the disease, while male dogs only need one copy from their mother to be affected. Therefore, male dogs are more commonly symptomatic. Each male pup born to a carrier female has a 50% chance of inheriting the disease. Female dogs that are not carriers do not have an increased risk of producing affected pups. Genetic testing is crucial for responsible breeding practices, especially since female carriers typically do not show symptoms. To avoid producing affected puppies and eliminate the mutation from breeding lines, it is essential not to breed two known carriers. Dogs that are not carriers do not pose a risk of producing affected offspring.