Inherited thrombophilia includes factor V G1691A-Leiden mutation (18 cases; 15.78%), prothrombin G20210A gene mutation (three cases; 2.63%), MTHFR gene polymorphism C677T (44 cases; 38.59%) and A1298C (16 cases; 14.03%), PAI-1 675 4G/5G gene mutation (49 cases; 42.98%), as well as hyperhomocysteinemia (40 cases; 35.08%) was found at 60 patients (52.63%) from the first group. The gene discussed is MTHFR; the disease is Rare hereditary thrombophilia.