Elliptocytosis

Common Symptoms

Canine elliptocytosis is a rare inherited blood disorder. Normal red blood cells are round in shape but red blood cells in affected dogs appear oval-shaped and can have serrated edges. An affected dog may present with mild Anemia and may be smaller than its littermates. Severe health complications have not been reported in affected dogs.

Breed-Specific Information for the Chow Chow

Chow Chows are included as a breed susceptible to elliptocytosis due to a publication describing the condition in an affected Chow Chow/Labrador Retriever mixed breed dog. The parental history of the affected dog was not available; therefore the breed of the affected parent is unknown. The frequency of the causal Mutation in the general Chow Chow population is unknown.

Testing Tips

Genetic testing of the SPTB gene in Chow Chows will reliably determine whether a dog is a genetic Carrier of canine elliptocytosis. Canine elliptocytosis is inherited in an Autosomal Dominant manner in dogs meaning that they only need to inherit one copy of the mutated gene to develop the disease. Dogs identified to have the genetic change are expected to have features of the disease, though symptoms can be very mild and dogs may appear healthy. Each pup that is born to a single affected parent has a 50% chance of inheriting one copy of the SPTB gene Mutation and having the disease. If both parents are affected, the chance of having affected offspring increases to 75-100%. Reliable genetic testing is important for determining breeding practices. In order to eliminate this mutation from breeding lines and to avoid the potential of producing affected pups, breeding of known carriers is not recommended. Chow Chows that are not carriers of the mutation have no increased risk of having affected pups.

There may be other causes of this condition in dogs and a normal result does not exclude a different mutation in this gene or any other gene that may result in a similar genetic disease or trait.

References

• Di Terlizzi R, Gallagher PG, Mohandas N, Steiner LA, Dolce KS, Guo X, Wilkerson MJ, Stockham SL. Canine elliptocytosis due to a mutant beta-spectrin. Vet Clin Pathol. 2009 Mar; 38(1):52-8. [PubMed: 19228356]