Fibrinogen Matsumoto II: gamma(308)Asn->Lys(AAT->AAG) mutation associated with bleeding tendency

Fibrinogen Matsumoto II is a hereditary dys-fibrinogenaemia identified in a woman with Basedow's disease and a bleeding tendency. Coagulation tests of the patient's plasma revealed a prolonged thrombin time and a decreased fibrinogen level determined by functional method. Release of fibrinopeptide A and B was normal, whereas fibrin monomer polymerization was delayed. Fibrinogen gamma-chain gene of the propositus was heterozygous for a missense mutation that resulted in Asn --> Lys substitution at codon 308. Though the same amino acid substitution was also attributed to fibrinogen Kyoto I and Bicetre II, fibrinogen Matsumoto II showed different clinical manifestations from them.