Phosphofructokinase Deficiency (PFK)

Description

Phosphofructokinase Deficiency (PFKD) is an autosomal recessive disorder that affects Cocker Spaniels. Autosomal recessive disorders are disorders that can be passed from either parent and require two copies of the gene to show symptoms. This metabolic disorder does not allow the PFK enzyme to function properly, affecting the energy-producing glycolytic (sugar) cycle and destroying red blood cells in the process. A lack of oxygen-carrying red blood cells and glucose (sugar) leads the dog to experience anemia and exercise intolerance. The dog may also feel cramping of the muscles.

This condition is treatable with bone marrow transplantation, although the procedure is extremely expensive. Dogs are able to have a normal quality of life if PFKD is properly managed. Dogs should be kept in low-stress environments and should not be allowed to strenuously exercise.

Because PFKD is a recessive disorder, a dog must have two copies of the mutation in order for the disease to manifest. This means that a dog can have one copy of the mutation and not experience any signs or symptoms of PFKD. This dog would be known as a carrier. The carrier can then pass on either the normal gene or the mutated gene to any offspring. If two carriers are bred, there is a 25% per puppy that they will develop symptoms of PFKD. It is estimated that at least 10% of the Cocker Spaniel population are obligate carriers. This makes it especially important to test Cocker Spaniels before breeding.