The symptomatic five families show three different mutations of the Arg596, and namely: prothrombin Yukuhashi Arg596Leu,237prothrombin Belgrade and Amrita Arg596Gln,238, 239and prothrombin Padua 2 Arg596Trp.240Although all these hereditary thrombophilias are rare, clinicians ought to keep in mind these novel mutations when dealing with patients or families with unexplained history of recurrent VTE. Here, F2 is linked to Rare hereditary thrombophilia.