FREQUENCY OF THE 20210-G-]A MUTATION IN THE 3'-UNTRANSLATED REGION OFTHE PROTHROMBIN GENE IN 35 CASES OF CEREBRAL VENOUS THROMBOSIS

Background and Purpose-A novel sequence variation in the 3'-untranslat ed region of the prothrombin (factor II) gene (nucleotide 20210 G-->A) has been recently described as a risk factor for deep vein thrombosis and pulmonary embolism. It is found in approximate to 1% to 4% of hea lthy subjects. We studied the frequency of this factor II variant in p atients with cerebral venous thrombosis.Methods-The 20210A allele of t he prothrombin gene was studied after DNA extraction, polymerase chain reaction amplification, and HindIII digestion in 35 patients with mag netic resonance imaging or angiographically confirmed cerebral venous thrombosis (23 women and 12 men, aged 11 to 71 years). Results-Two pat ients (5.7%) had the 20210A allele of the prothrombin gene. Both had o ther risk factors for thrombosis (use of oral contraceptives and of in trathecal steroids). Conclusions-The 20210A allele of the prothrombin gene in association with other prothrombic factors may increase the ri sk of cerebral venous thrombosis, but case-control studies will be nec essary to clarify these associations.