These authors contributed equally to this manuscript.
A novel missense mutation responsible for factor VII deficiency in research Beagle colonies
Article first published online: 8 SEP 2006
Journal of Thrombosis and Haemostasis
Volume 4, Issue 12, pages 2616–2622, December 2006
How to Cite
CALLAN, M. B., ALJAMALI, M. N., MARGARITIS, P., GRIOT-WENK, M. E., POLLAK, E. S., WERNER, P., GIGER, U. and HIGH, K. A. (2006), A novel missense mutation responsible for factor VII deficiency in research Beagle colonies. Journal of Thrombosis and Haemostasis, 4: 2616–2622. doi: 10.1111/j.1538-7836.2006.02203.x
- Issue published online: 8 SEP 2006
- Article first published online: 8 SEP 2006
- Received 25 July 2006, accepted 31 August 2006
- factor VII deficiency;
- missense mutation
Summary. Background: Canine factor VII (cFVII) deficiency, an autosomal recessive trait originally identified in research Beagles, is associated with a mild to moderate bleeding tendency. Objective: Our aim was to identify and characterize the mutation causing cFVII deficiency. Methods: In order to sequence the coding regions of the cFVII gene, we cloned the cFVII cDNA. Genomic DNA and plasma from FVII-deficient Beagles and obligate carriers were utilized. Results: In all FVII-deficient dogs, we identified a single causative G to A missense mutation in exon 5, encoding the second epidermal growth factor-like domain, resulting in substitution of glycine 96 by glutamic acid, with plasma FVII coagulant activity of ≤ 4% in affected Beagles. In vitro expression indicated that the majority (96%) of cFVII-G96E protein was retained intracellularly. In addition, analysis of purified recombinant wild-type and mutant cFVII proteins demonstrated reduced activity of the mutant (< 2%) compared with wild-type. Rotational thromboelastometry revealed a severe impairment of clotting activity in affected Beagles, and heterozygotes also exhibited changes in coagulation-based assays. Using a mutation-specific polymerase chain reaction/restriction digest that allows rapid identification of the G96E mutation, we surveyed a US research Beagle colony and identified a mutant allelic frequency of 31%. Conclusions: We have identified a single causative mutation for cFVII deficiency that may have implications for pharmacotoxicologic research, because reduced FVII coagulant activity may alter hemostatic and/or cardiovascular endpoints in this commonly used animal species.