When hereditary risk factors were analyzed one by one; factor V Leiden mutation, protein C deficiency and genetic changes specified under the name of other prothrombotic risk factors in our study (activated protein C resistance, factor XIII deficiency, plasminogen activator inhibitor-1 deficiency, GP2b3A mutation) were observed more frequently in the recurrent PTE group (Table 2). The gene discussed is SERPINE1; the disease is protein c deficiency.