Molecular diagnostics of inherited thrombosis.

Thrombophilia can best be defined as a disorder of coagulation that contributes to a predisposition towards thrombosis. Although the term thrombophilia has been used to describe arterial thrombosis, its most common usage has been in reference to venous thromboembolism (VTE). Thrombophilia can be a consequence of both acquired and inherited or genetic causes. Acquired causes include conditions such as surgery, cancer, and prolonged immobilization, while genetic causes have been linked to the inherited deficiencies of antithrombin, protein C, and protein S. The identification of the genetic basis of these inherited causes of thrombophilia ushered in a new way of thinking about thrombosis and the importance of its genetic component. Interest in the genetic basis of VTE was accelerated with the subsequent discovery of factor V Leiden, prothrombin G20210A, and MTHFR C677T. These single nucleotide polymorphisms (SNPs) and other genetic variants associated with VTE have become fixtures in the molecular diagnosis of inherited thrombophilia. Because of the large volume of current and anticipated future genetic testing, there has been a push to develop many different genotyping methods which are now used in both clinical and research settings. The identification of new genetic variants that may either directly or indirectly affect coagulation or the anticoagulant pathway, may greatly advance the understanding and clinical management of thrombophilia.