The most common causes of hereditary thrombophilia are: antithrombin deficiency, protein C deficiency, protein S deficiency, disturbances in fibrinogen levels, elevated homocysteine levels, factor II mutation (F2 c.*97G > A; previous nomenclature G20210A) and factor V Leiden mutation (HGVS nomenclature: F5 c.1601G > A) [71]. The gene discussed is F5; the disease is Rare hereditary thrombophilia.