Genetic Test for Pyruvate Kinase (PK) Deficiency

Description:

Pyruvate kinase (PK) is an enzyme critical to the anaerobic glycolytic pathway of energy production in the erythrocyte.  If erythrocytes are deficient in PK they are unable to sustain normal cell metabolism and hence are destroyed prematurely.  This deficiency manifests as a hemolytic anemia of variable severity with a strong regenerative response.  In dogs, the anemia is always severe (PCV 10-20%).  Also associated with the disease in dogs is a progressive myelofibrosis and osteosclerosis of unknown etiology and this feature, along with liver failure, is the major cause of death in affected dogs.  The life expectancy of affected dogs is shortened and most die before 4 years of age.  The dog breeds involved are the Basenji, Beagle, Dachshund, Eskimo, West Highland White Terriers and the Beagle.  In all breeds the disease is inherited as an autosomal recessive condition.  Heterozygotes (carriers) do not have any clinical signs of disease and lead normal lives.  They are able to propagate the mutant allele throughout the population however and it is therefore important that carrier animals be detected prior to breeding.  PK deficiency can be detected, using molecular genetic testing techniques, in the Basenji, Beagle, Dachshund, Eskimo, West Highland White Terrier and the Cairn Terriers.  These tests identify both affected and carrier animals.

Clinical Signs:

The clinical signs of disease reflect the anemic status of the animal and include exercise intolerance, weakness, heart murmur and splenomegaly.  The anemia is macrocytic, hypochromic and highly regenerative in dogs. Radiographs reveal generalized abnormalities in bone density including intramedullary mineralisation of the long bones suggestive of progressive osteosclerosis in dogs.

Information taken from the PennGen website:  http://research.vet.upenn.edu/DiseaseInformation/tabid/545/Default.aspx