This condition is inherited in an autosomal dominant manner. The prevalence is thought to be 0.2-0.4% in the general population.
The genetic basis of antithrombin deficiency is heterogeneous:
- there may be normal antigenic levels of the protein, in which case there is a functional defect in the antithrombin
- reduced antigenic levels of antithrombin suggest a defect in the synthesis or stability of the protein