Antithrombin Cambridge Ⅱ(A384S) Mutation Frequency And Antithrombin Activity Levels In Venous Thrombosis And Cerebral Infarction Patients

Objective We investigated the prevalence of antithrombin CambridgeⅡmutation (A384S) and the antithrombin activity level in the chinese patients with venous thrombosis and cerebral infarction and analyzed their role in the venous and arterial thrombosis.Methods 120 patients with venous thrombosis,150 patients with cerebral infarction and 110 normal subjects were studied.The antithrombin activity was determined with chromogenic assay.Genomic DNA was purified by standard procedures from the WBC in blood samples.The target DNA fragment was amplified by polymerase chain reaction(PCR),and the A384S mutation was identified with PCR-allele-s pecific restriction assay using PVUⅡ.Results 1:No A384S mutation was identified in the normal subjects and patients. with venous thrombosis and cerebral infarction,which suggested that there is little correlation with this mutaion and venous/arterial thrombosis,and A384S mutation is not a genetic risk factor for venous and arterial thrombosis.2:The average antithrombin activity of the venous thrombosis group was 91.37±16.15%,with 101.69±13.40%of the cerebral infarcion group and 102.68±13.10%of the normal subjects.The antithrombin activity of the venous thrombosis group was significantly lower campared to the normal subjects. 3:8 antithrombin deficiencies (6.7%) was identified in 120 pa tients with venous thrombosis.And there was no antithrombin deficiency in the patients with cerebral infarction. The venous thrombosis patients with antithrombin deficiency had earlier onset (38Y vs 49Y) than those of without antithrombin deficiency.Conclusion Antithrombin deficiency is a major genetic risk factor for venous thrombosis in Chinese people.And there is no significant association between antithrombin deficiency and cerebral infarction.The prevalence of antithrombin CambridgeⅡmutation (A384S) in the normal chinese people is extremely low,and our study failed to find A384S mutation both in the patients with venous thrombosis and the patients with cerebral infarction,which suggested that antithrombin CambridgeⅡA384S mutation was not a genetic risk factor for the arterial and venous thrombosis.