Phosphofructokinase Deficiency (PFK/PFKM)
last updated 15/1/2025
Also called Glycogen Storage Disease VII,
Glycogen Storage Disease VII, PFK Deficiency is a metabolic disorder with a genetic basis
Breed-Specific Information, the English Cocker Spaniel is included as a breed susceptible to glycogen storage disease VII, PFK deficiency because of its close relatedness to the (American) Cocker Spaniel, which is known to develop this disease due to PFKM gene mutation.
The frequency of the causal mutation in the general English Cocker Spaniel population is unknown.
Phosphofructokinase Deficiency (PKFD) is an autosomal recessive disorder. This metabolic disorder does not allow the PFK enzyme to function properly, affecting the energy-producing glycolytic cycle and destroying red blood cells.
A lack of oxygen-carrying red blood cells and glucose leads the dog to experience anaemia and exercise intolerance. The dog may also feel cramping of the muscles.
Muscle phosphofructokinase (PFK) deficiency (Tarui's disease), or glycogen storage disease type 7 (GSD7), is a rare form of glycogen storage disease characterized by exertional fatigue and muscular exercise intolerance.
Disruption of the PFKM gene can result in a Phosphofructokinase deficiency that leads to muscles that fatigue very easily, because they cannot use energy very efficiently. Affected dogs display muscle weakness, an inability to exercise properly, or muscle cramping.
Phosphofructokinase
deficiency has been found in
English Springer Spaniel, American
Cocker Spaniel and their cross species, also in whippets A second mutation has been identified in Wachtelhund
Reading
I can find no evidence of PFK in English Cocker Spaniels - everything to date is regarding Springers or American Cocker Spaniels! And there is very little data even for these.
what I did find was US based or referred to American Cocker Spaniels that were detected as having PFKM
This could be a case where the name anomaly has occurred and creates havoc
Note Some lab's including Orivet now includes this test as part of their full breed panel, undertake the testing with caution, as the results may not be specifically relevant to our (English) cocker spaniels.
There is a link below regarding my experience with using tests that are not fully proven or peer reviewed.
Research Notes on pfk
I have concerns about this test, until it is proven to have definitely occurred, we're just wildly guessing, which can do more harm than good.
CASE REPORT Inherited phosphofructokinase deficiency in an American Cocker Spaniel
Animal Genetics 1986;17(1):15-23 Autosomal recessive inherited phosphofructokinase deficiency in English springer spaniel dogs
doi: 10.1111/j.1365-2052.1986.tb03184.x
Review J Am Vet Med Assoc
. 1987 Aug 15;191(4):453-9
Hemolysis caused by phosphofructokinase deficiency in English springer spaniels: seven cases (1983-1986)
NUCLEIC ACIDS, PROTEIN SYNTHESIS, AND MOLECULAR GENETICS| VOLUME 271, ISSUE 33, P20070-20074, AUGUST 1996 Molecular Basis of Canine Muscle Type Phosphofructokinase Deficiency
Diseases of the Blood WSAVA 2002 Congress Urs Giger, Diplomate ACVIM & ECVIM
OMIA:000421-9615 : Glycogen storage disease in the English springer spaniel, American cocker spaniel and Whippets.
Glycogen storage disease Type IV, found in English Spring Spaniels, results in haemolytic anaemia, a condition in which red blood cells are destroyed, and haemoglobinuria, a condition in which the protein hemoglobin (which helps transport oxygen throughout the body) is abnormally highly concentrated in the patient’s urine.
PFK Around The World
Genetic testing has proven to be a invaluable tool and an intrinsic part of breeding healthy cockers and reducing the likelihood of disease.
Not included in any cocker spaniel databases
last checked for data January 2025