Their prevalences in general population vary: 0,2%–0,4Z% for protein C deficiency, 0,2% for protein S deficiency, 0,02%for antithrombin deficiency and 4%–5%  for factor V Leiden, 1:5.000 persons being homozygous for factor V Leiden [3]. Here, F5 is linked to hereditary antithrombin deficiency.