Complement 3 Deficiency (Brittany)

Canine C3 deficiency is a hereditary disorder affecting the Brittany Spaniel. The Complement Component C3 is an important protein of the immune system and is crucial for dog's ability to prevent bacterial infections. The mutation prohibits the formation of protein's functional units and the chain of one's defence mechanisms is broken. Signs of C3 deficiency often first appear in young dogs. Affected individuals show a predisposition to recurrent bacterial infections and to type 1 membranoproliferative glomerulonephritis. They suffer from skin infections, infections of the uterine tract and respiratory infections like pneumonia. As a result of this condition kidney disease can develop early in life where dogs show signs of decreased appetite and increased thirst and urination. This often leads to chronic kidney failure and shortened life span. Young dogs suffering from this disease are also very susceptible to developing hereditary muscle disease.

Inheritance: autosomal recessive

Mutation: C3 gene

Genetic test: The method used for genetic testing is extremely accurate and allows complete differentiation between affected animals, carriers and healthy dogs. DNA testing can be done at any age.