FVII deficiency in Scottish Deerhounds causing a bleeding disorder

Factor VII Deficiency Scottish Deerhounds DNA Test Submission Form

Description:
Several hereditary bleeding disorders have been identified in many different canine breeds and involve clotting (coagulation) factor deficiencies, platelet disorders, and von Willebrand disease. Coagulation factor VII (FVII) deficiency has been known to occur in Beagles for decades, and there are a few reports of FVII deficiency in other breeds. Very recently hereditary FVII deficiency was identified in a few Scottish Deerhounds with excessive bleeding following surgery. A DNA test to identify the mutation responsible for FVII deficiency in Scottish Deerhounds has been developed at the University of Pennsylvania.

Dogs with hereditary FVII deficiency may exhibit an increased bleeding tendency following trauma or surgery or rarely appear to develop spontaneous bleeding. There are few reports of severe bleeding requiring blood transfusions, and some FVII-deficient dogs may remain unrecognized. As this is an autosomal recessive disorder, the diseased/mutant gene (allele) may be unknowingly passed on through generations not only via asymptomatic carriers but also affected dogs, as they may not show obvious signs. Carriers have one mutant and one normal gene and appear clinically normal, but they can pass the defective gene to their offspring. Only a small number of Scottish Deerhounds have been tested thus far, and hence the frequency and bleeding tendency remain to be elucidated.

Screening Scottish Deerhounds with a clotting test (PT assay) may suggest FVII deficiency, and measurement of plasma FVII coagulant activity could confirm a diagnosis of FVII deficiency. Results of the PT assay are normal for carriers, and measurement of plasma FVII coagulant activity will not accurately identify carriers, as there is overlap of FVII activities between carrier and normal dogs.

A mutation-based DNA test to screen Scottish Deerhounds (and Beagles) for FVII deficiency has been developed (Dr. Beth Callan, principal investigator) and has then been established at the Josephine Deubler Genetic Disease Testing Laboratory of the University of Pennsylvania School of Veterinary Medicine (Dr. Urs Giger, director; Mr. Adam Seng, Research Specialist). This test can clearly identify affected, carrier, and normal (also known as clear) Scottish Deerhounds. We recommend testing of any Scottish Deerhound with signs of bleeding, as well as its relatives.

The Josephine Deubler Genetic Testing Laboratory at the University of Pennsylvania is offering screening for FVII deficiency in Scottish Deerhounds. The cost is $75 per sample. Samples suitable for this DNA test include 1-2 mls EDTA-anticoagulated blood (preferable) or 2-3 cheek swabs (obtained with special cytology brushes). Test submission forms may be downloaded from our website http://www.vet.upenn.edu/penngen . Cytology brushes may be requested by contacting Mr. Adam Seng (215-898-3375; penngen@vet.upenn.edu ). For more information on canine FVII deficiency, please contact Dr. Beth Callan (215-898-3999; callan@vet.upenn.edu ) or Dr. Urs Giger (215-898-8830; penngen@vet.upenn.edu ). Blood and dried cheek swab samples, along with test submission forms and pedigrees, may be submitted in a ziploc bag to Dr. Urs Giger/FVII Rm 4006, Ryan Veterinary Hospital, University of Pennsylvania, 3900 Spruce Street, Philadelphia, PA, 19104-6010. Test results are generally available within 3 weeks of receipt of samples and are sent only to submitter of samples. All information is kept strictly confidential.