Molecular diagnosis of hereditary thrombotic disorders.

Deep vein thrombosis (DVT) can be the result of coagulation pathway defects at the molecular level or damage to the vascular endothelium. Some of the acquired causes of DVT include malignancy, trauma, prolonged immobilization, and pregnancy (1). Thrombophilia can be owing in part to both acquired and inherited defects. The relative risk for thrombosis is increased by estrogen replacement therapy (2) and homocysteinemia (3). Homocysteine metabolism is influenced by the use of alcohol, anticonvulsant drugs, cyclosporine, methotrexate, inadequate dietary vitamin B(12), folate and pyridoxine intake, organ transplantation, and reduced creatinine clearance (4-8). Similar to venous thrombosis, homocysteinemia has genetic factors that influence susceptibility (9-11).