Basset Hound Thrombopathia
Basset Hound Thrombopathia (BHT) was first described by Johnstone and Lotz in 1979. Since that time
investigators at Cornell, Michigan State, and Auburn University have studied the disorder in affected and carrier
Basset hounds in attempts to understand the functional, biochemical, and molecular bases for the disorder. The
disorder is due to a congenital/inherited signal transduction defect in platelets. Platelets are small, circulating
cytoplasmic fragments that are the first line of defense in stopping the flow of blood from injured blood vessels.
An important aspect of platelet function is their ability to stick to each other and plug holes in damaged vessels
until blood clotting and tissue repair can occur. The platelets of dogs with BHT are defective in their ability to
stick to each other due to the inability of the platelets to transmit internal signals properly. Therefore, these
individuals are at increased risk for spontaneous hemorrhage and they are also at high risk for excessive
hemorrhage as a result of injury or surgery. Affected Basset hounds experience spontaneous mucosal type
bleeding (including gingival bleeding, particularly during permanent tooth eruption, gastrointestinal bleeding,
urinary tract bleeding, and nose bleeds), and petechial and ecchymotic hemorrhages of the skin (bruising that
can range from small, pinpoint lesions to lesions as large as a half-dollar or larger) and hemorrhage at the tips of
the ears secondary to trauma. Gastrointestinal bleeding may or may not be apparent. If bleeding is severe, the
stools will appear black and tarry. Gastrointestinal bleeds can also be slow and insidious (microscopic and not
visibly apparent) resulting in iron deficiency anemia with time.
For many years the disease could not be diagnosed without bringing dogs to a testing facility that specialized in
studying platelet function disorders in animals. Although these methods were accurate in diagnosing affected
dogs, the methods could not readily identify carriers of the disease. Carrier detection is vital in controlling spread
of inherited defects and DNA testing is the only reliable method of detecting these animals. During the summer
of 2006, the molecular basis for BHT was determined at Auburn University. A mutation was found in a gene that
encodes for a signal transduction protein vitally important in transmitting signals that result in normal platelet
aggregation and granule release. By using DNA testing, affected and carrier Basset hounds can now be
identified by submitting a blood sample through the mail.
• Johnstone IB, Lotz F: An inherited platelet function defect in Basset hounds Can Vet J 20:211-215, 1979.
• Catalfamo JL, Raymond SL, White JG, Dodds WJ: Defective platelet-fibrinogen interaction in hereditary
canine thrombopathia. Blood 67:1568-1577, 1986.
• Boudreaux MK, Dodds WJ, Slauson DO, Catalfamo JL: Evidence for regulatory control of canine platelet
phosphodiesterase. Biochem Biophys Res Commun 140(2):580-594, 1986.
• Boudreaux MK, Dodds WJ, Slauson DO, Catalfamo JL: Impaired cAMP metabolism associated with
abnormal function of thrombopathic canine platelets. Biochem Biophys Res Commun 140:595-601, 1986.
• Patterson WR, Estry DW, Schwartz KA, Borchert RD, Bell TG: Absent platelet aggregation with normal
fibrinogen binding in Basset hound hereditary thrombopathy. Thromb Haemostas 62(3):1011-1015,1989.
• Boudreaux MK, Catalfamo JL, Klok M: Calcium-diacylglycerol guanine nucleotide exchange factor I gene
mutations associated with loss of function in canine platelets. Transl Res 150(2):81-92, 2007.
Specimen requirements: At least 1ml EDTA whole blood (purple top tube). Do not cross contaminate samples during
collection particularly if more than one dog is collected at the same time. Label all specimens clearly. Protect the tubes to
prevent breakage during shipping. All methods of shipping are acceptable. Blood samples do not require ice.
Ship to: Hemostasis Laboratory, Peter W. Christopherson
166 Greene Hall
Auburn University, AL 36849-5519
Fee for testing: $125.00 (payment options listed below)
Make checks payable to: Auburn University, Department of Pathobiology
Credit Card payments accepted by phone: 334-844-2690
Wire transfers: Email email@example.com for wire transfer instructions