Dog Phosphofructokinase Deficiency (PFKD)
Acronym: | PFKD, M-PFKD, GSD VII |
Gene: | PFKM |
Mutation: | c.2228G>A |
Inheritance: | Autosomal recessive |
Sample type: | CHS (Cheek Swab), WBE (Whole Blood EDTA) |
Genetics and characteristics
Dog Phosphofructokinase Deficiency PFKD is a genetic disorder that prevents the phosphofructokinase enzyme from functioning properly. It is a rare inherited glycogen storage disease that causes a metabolic myopathy and compensated hemolytic disorder. The affected dogs have a chronic compensated hemolytic disorder and exertional myopathy. However, these animals most often present with hemolytic crises due to the high capacity of the dog for aerobic work and the intrinsic alkaline fragility of erythrocytes. Dogs with M-PFK deficiency have 6–22% of normal erythrocyte PFK activity and 1–4% of normal muscle PFK activity.
Dog Phosphofructokinase Deficiency is a recessive disorder, so a dog can be a carrier of PFK deficiency and not display any symptoms associated with the disorder. It is estimated that at least 10% of the cocker spaniel population are carriers, which makes the importance of genetic testing even higher. If two carriers of PFKD are bred, there is a 25% chance that the offspring could receive the mutated allele from each parent and be affected by the disease.
Results Reported As
Test Result |
Interpretation of test result |
CLEAR |
Tested mutation was not detected in animal with „clear“ result. Animal tested as clear has wild-type allele in homozygous state (i.e. two pairs of healthy alleles). It will not develop disease caused by tested mutation.* It will pass only wild-type allele to its offspring. |
CARRIER |
Tested mutation was detected in animal with „carrier“ result. Animal tested as carrier has one wild-type and one mutation allele, it is in heterozygous state. It will not develop disease caused by tested mutation.* It can pass wild-type or mutation allele to its offspring. |
AFFECTED |
Tested mutation was detected in animal with „affected“ result. Animal tested as affected has two copies of mutation alleles affecting the gene. It is likely the animal will experience a genetic disorder due to this mutation.** It will pass only mutation allele to its offspring. |
*Test excludes only tested mutation but not possible unknown mutations or factors that can lead to similar condition/symptoms.
** Potential unknown mutations or multiple other factors can possibly affect the likelihood of experiencing a genetic disorder.
References:
Smith, B.F., Stedman, H., Rajpurohit, Y., Henthorn, P.S., Wolfe, J.H., Patterson, D.F., and Giger, U. (1996). Molecular Basis of Canine Muscle Type Phosphofructokinase Deficiency. J. Biol. Chem. 271, 20070–20074.