What is Feline Hemophilia

Feline Hemophilia, also known as Hemophilia B or "Christmas disease," is a rare genetic bleeding disorder that affects cats. It is caused by a deficiency of clotting factor IX, a protein that plays a crucial role in the blood clotting process. Without sufficient factor IX, cats with hemophilia B experience prolonged bleeding after injuries or surgeries, as their blood is unable to form stable clots.

Genetic Basis and Transmission

Feline Hemophilia is inherited as an X-linked recessive genetic disorder. This means that the defective gene responsible for the disorder is located on the X chromosome. Since males have only one X chromosome (XY), a single copy of the defective gene is enough to express the disorder in them. Females, on the other hand, have two X chromosomes (XX), so they need two copies of the defective gene to express the disorder. Female cats carrying one copy of the defective gene are carriers and do not usually show symptoms.


The symptoms of Feline Hemophilia can vary in severity and may include:


Diagnosing Feline Hemophilia involves a combination of clinical signs, bleeding history, and specific blood tests. A clotting profile, including tests for clotting times and factor IX activity, can confirm the presence of the disorder and help determine its severity.


The main goal of treating Feline Hemophilia is to control bleeding episodes and improve the cat's quality of life. This is usually done by administering clotting factor IX to replace the deficient protein. The treatment may involve regular injections of factor IX or infusions as needed, particularly after injuries or surgeries. Additionally, supportive care such as wound care and avoiding situations that could lead to bleeding is crucial.

Genetic Variants

There are different genetic variants of Feline Hemophilia B, each associated with varying levels of factor IX deficiency. Some cats may have milder forms of the disorder, while others may experience more severe bleeding episodes. Specific genetic variants responsible for Feline Hemophilia B were not extensively documented in the public domain. Unlike in humans, where the specific genetic mutations responsible for various forms of hemophilia are well-documented, the genetic variants for Feline Hemophilia B may not have been widely characterized or cataloged.

Current Understanding

Feline Hemophilia has been studied primarily in the context of veterinary medicine. Research has provided insights into the genetic basis of the disorder, diagnostic methods, and treatment options. However, it's important to note that advancements in research and medical knowledge may have occurred since then. For the most current information on this specific subject I recommend you speak to a specialist in this exact field.