Genomische Diagnostik thrombophiler Gerinnungsstörungen bei Frauen

Abstract

The detection of the DNA-sequence of human coagulation factors and inhibitors has introduced the possibility of differentiated mutation analysis in patients with venous thrombosis. Since venous thromboembolism is a multifactorial disease, women are at an increased risk to develop venous thrombosis due to hormonal contraception, during pregnancy and the puerperium. In addition, pregnancy complications like early or late fetal loss, pregnancy-induced hypertensive disorders and very recently recurrent embryo implantation failure have been suspected to be associated with thrombophilia. Therefore, it is of major importance to define inherited thrombophilic disorders, in which genetic diagnosis is of clinical relevance. While most of the genetic defects described so far represent a risk factor for venous thrombosis, only a minority of these defects actually needs DNA analysis to be detected: mutation analysis is clinically relevant, when factor V Leiden mutation is suspected, because relative risks concerning venous thrombosis as well as pregnancy complications clearly differ between homozygote and heterozygote forms of this frequently observed mutation. Similarly detection of the prothrombin mutation G20210A is of clinical relevance, although data for the very rarely observed homozygote variant are not sufficiently available. In contrast, detection of the homozygote variant of the MTHFR-mutation C677T is not useful, since clinical relevance could not be proven in a majority of studies concerning women specific risk situations. Inherited deficiencies of antithrombin, protein C and protein S are rare with high rates of different mutations. Genetic analysis seems only useful in patients with wide intraindividual variations of coagulation inhibitor activities. Genetic analysis concerning the PAI-1 4G/5G polymorphism or the factor XIII Val34Leu polymorphism can not be recommended in women specific risk situations because of insufficient data.