Erythrocyte Pyruvate Kinase Deficiency in West Highland White Terriers
Pyruvate kinase deficiency is an inherited disease resulting from a defect in a gene for an enzyme, pyruvate kinase, in red blood cells. The clinical signs of the disease include severe haemolytic anaemia and disorders of the bone marrow and the liver. The disease affects a number of breeds, and 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. Individuals with one copy of the defective gene and one copy of the normal gene, called carriers, show no symptoms but can pass the defective gene onto their offspring. When two apparently healthy carriers are crossed, 25% (on average) of the offspring will be affected by the condition with a further 50% themselves being carriers.
The genetic defect underlying this condition in West Highland White Terriers was recently shown (by Dr Barbara Skelly and co-workers at the University of Pennsylvania) to be a deletion of a small segment of DNA within the gene. The Animal Health Trust is now offering a DNA test for this disease distinguishing affected, carrier and normal individuals. The test directly probes the DNA of the pyruvate kinase gene itself, and so does not suffer from the uncertainty associated with some other methods of testing. The DNA test provides definitive information on the genetic status of this disease and will give breeders the information to eradicate the disease from their lines.
The test can not only diagnose West Highland White Terriers affected with this disease but can also detect those dogs which are carriers, showing no symptoms of the disease but able to produce affected pups. It is important to eliminate carriers from a breeding population since they represent a hidden reservoir of the disease that can produce affected dogs at any time.
This test requires 2mls EDTA blood. Samples for testing should be sent, together with a completed DNA Testing form and payment of £65 inc VAT (cheque or credit card) for each sample to Genetic Services, Animal Health Trust, Lanwades Park, Kentford, Newmarket, Suffolk CB8 7UU.
DNA testing forms can be downloaded by clicking here.
Enquiries should be made to Symone Ingram telephone +44 (0) 8700 509144 or fax +44 (0) 8700 502461 or via e-mail to dnatesting@aht.org.uk.
