Sanger sequencing revealed three other patients with either the thrombophilia predisposing regulatory prothrombin gene F2 variant c.20210G>A, the known loss-of-function variant in the factor V-Leiden gene F5 c.1691G>A p.Arg506Glu or both variants together in a heterozygous state. The gene discussed is F5; the disease is Rare hereditary thrombophilia.