|Other Names:||Phosphofructokinase deficiency, GSD VII, PFK deficiency|
Glycogen storage disease VII (wachtelhund type) is an inherited metabolic disorder affecting dogs. Glycogen is the primary source of stored energy for the body. Affected dogs have insufficient activity of the phosphofructokinase Enzyme which breaks down glycogen for energy. Deficiency of this enzyme results primarily in easily damaged red blood cells (hemolysis) and also damage to skeletal muscle cells. Affected dogs can have pale gums from decreased numbers of red blood cells (Anemia) and may be lethargic or unwilling to exercise. After strenuous activity or periods of excitement or stress, affected dogs may have symptoms of hemolysis and muscle cell damage, which can include red or brown urine, muscle cramping, and jaundice. Affected dogs generally have a normal life expectancy, but may have recurrent episodes of hemolysis after exercise and muscle wasting progressing to an inability to walk.
Genetic testing of the PFKM gene will reliably determine whether a dog is a genetic Carrier of glycogen storage disease VII (wachtelhund type). Glycogen storage disease VII (wachtelhund type) is inherited in an Autosomal Recessive manner in dogs meaning that they must receive two copies of the mutated gene (one from each parent) to develop the disease. In general, carrier dogs do not have features of the disease but when bred with another carrier of the same Mutation, there is a risk of having affected pups. Each pup that is born to this pairing has a 25% chance of inheriting the disease and a 50% chance of inheriting one copy and being a carrier of the PFKM gene mutation. 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 to each other is not recommended. Dogs 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.
- Gultekin GI, Raj K, Lehman S, Hillstrom A, Giger U. Missense mutation in PFKM associated with muscle-type phosphofructokinase deficiency in the Wachtelhund dog. Mol Cell Probes. 2012 Dec;26(6):243-247. [PubMed: 22446493]
- Hillstrom A, Tvedten H, Rowe A, Giger U. Hereditary Phosphofructokinase Deficiency in Wachtelhunds. J Am Anim Hosp Assoc. 2011 Mar-Apr;47(2):145-50. [PubMed: 21311071]