The genetic analysis of eight families with hemophilia B in Mongolia: Identification of two novel mutation oleh Purevdorj Munkhuu, Munkhtsetseg Bazarragchaa, Purevdorj Ichinkhorloo, Ki‐Young Yoo, Enkh‐Amar Ayush, Ochbadrakh Batjargal, Erdenebayar Namjil, Sarantuya Jav, Erkhembulgan Purevdorj, Sodnomtsogt Lkhagvasuren