C106 - Canine Phosphofructokinase Deficiency

The enzyme PFK is important in energy metabolism in red blood cells and in skeletal muscle during intense exercise. Canine Phosphofructokinase Deficiency is an inherited disorder that causes premature breakdown (hemolysis) of red blood cells, and a reduced tolerance for exercise. Affected dogs have chronic mild anemia with intermittent bouts of acute hemolysis, often associated with intense exercise, overheating or prolonged barking. Affected dogs have a persistent mild anemia (low levels of red blood cells) for which they are generally able to compensate. Intermittently they will have acute episodes of red blood cell breakdown, when they become lethargic and weak. This is usually associated with intense exercise or excessive barking or panting. Their mucous membranes (eg. gums) are pale or jaundiced and they usually run a high fever. You may notice the urine is brown due to the excretion of blood breakdown products. At these times your dog will require veterinary attention.

Canine Phosphofructokinase Deficiency shows an autosomal recessive mode of inheritance; therefore two copies of the defective gene, one inherited from each parent, have to be present for a dog to be affected by the disease. Carriers (dogs with one copy of the mutant gene and one copy of the normal gene) have about one half normal enzyme activity in red blood cells and muscle tissue, and are clinically unaffected, but can pass the defective gene onto their offspring.

Based on clinical examination and blood tests, your veterinarian will diagnose hemolytic anemia (low levels of red blood cells due to increased breakdown) in your dog. Further DNA tests will be required to diagnose this specific condition. This DNA test provides the reliable identification of dogs that carry mutant gene(s). The DNA test allows a breeder to control the mutant gene frequency in American Cocker and English Springer Spaniels thus preventing the production of puppies affected with Canine Phosphofructokinase Deficiency. This DNA test accurately and specifically identifies normal, carriers (heterozygous) and affected dogs.