Prothrombin gene mutation (G20210A) in healthy Centenarians.

A recently described genetic variant of the prothrombin gene (G to A transition at nucleotide position 20210) is associated with an increased risk of venous thrombosis (1). The 20210A prothrombin allele may precipitate cerebral ischemia or myocardial infarction in young patients with known prothrombotic abnormalities (2, 3). Similarly, it has been demonstrated that factor V Leiden further increases the risk of venous thrombosis in patients with inherited coagulation disorders (4). However, there are marked ethnic variations in the prevalence of factor V Leiden, which has been reported to be absent in Korean population (5, 6). The prevalence of prothrombin gene variant may also be different among individuals of different racial groups. We therefore investigated the frequency of prothrombin gene variant (20210A) in patients with thrombosis and randomly selected patients without a history of thromboembolic disease. The patient study group (n = 154; 69 men and 85 women) included 109 unrelated individuals (median age 57 years, range 20-86 years) who had been referred due to the venous or arterial thrombotic events (21 deep vein thrombosis, 7 pulmonary embolism, 4 isolated mesenteric or portal veins, 62 stroke, 7 myocardial infarct, 8 peripheral artery obstructive diseases), and 45 patients without thrombotic episode. To identify the prothrombin gene variant (20210A), 142-bp DNA fragment was obtained by amplification of genomic DNAs, and then digested using the HindIII endonuclease, as previously described (7). None of the subjects within this study group were found to have the mutation. This finding suggests that, as for factor V Leiden (5, 6), the 20210A prothrombin mutation is very rare, among the Korean population. Further investigation is needed to determine whether the detection of 20210A prothrombin may be of value in subgroups of patients with thrombosis.