FIBRINOGEN GUARENAS .1. PARTIAL CHARACTERIZATION OF A NEW DYSFIBRINOGENEMIA WITH AN ALTERED RATE OF FIBRINOPEPTIDE RELEASE AND AN IMPAIRED POLYMERIZATION

A congenitally abnormal fibrinogen was isolated from the blood of a: young woman with ct severe bleeding diathesis. Coagulation tests showed a prolonged Thrombin and Reptilase(R) time partially corrected by Ca2+. Polymerization of thrombin induced preformed fibrin monomers was severely impaired. Thrombin caused the release of fibrinopeptides with normal retention times on HPLC. However, the rate of release was abnormally slow and the total amount of fibrinopeptide A (FpA) released reached only similar to 50% of the theoretical maximum. The rate and quantity of FpA release wets normal when Reptilase was used. Transmission Electron Microscopy (TEM) of Thrombin induced clots showed an altered clot structure characterized by a reduced mean fiber diameter. The mother hers ct polymerization defect similar to the propositus, her fibrinopeptide release is unaffected however. The father has a minor fibrinopeptide release defect suggesting the presence of two populations of fibrinogen. This study supports the idea: that the fibrinogen isolated from the propositus hers two defects inherited as separate genetic traits. This fibrinogen hers been named Fibrinogen Guarenas I.