background: hemophilia b is an x-linked recessive coagulation disorder caused by factor ix deficiency.  analysis of factor ix gene polymorphisms is considered the best approach for prenatal diagnosis and carrier detection of hemophilia b where the identification of gene mutation is not easily possible.   objective: to study the frequency of three factor ix-linked restriction fragment length pol...

Factor X is a vitamin K-dependent, liver-produced serine protease that serves a pivotal role in coagulation as the first enzyme in the common pathway to fibrin formation. Inherited factor X deficiency is a rare autosomal recessive bleeding disorder that is estimated to occur in 1:1,000,000 individuals up to 1:500 carriers. Several international registries of FX-deficient patients have greatly e...

X-chromosome inactivation is normally a random event that is regulated by the X chromosome itself. Rarely, females are affected by X-linked disorders from extremely skewed X-chromosome inactivation. Here, we report a family with hemophilia B with female expression through inherited X skewing that appears to be independent of either X chromosome. This finding suggests the possibility of a domina...

T congenital factor X (FX) is a plasmatic glycoprotein, which plays a crucial role in coagulation. Its deficit is among rare causes of the hemorrhage in child. It could be acquired or congenital. The main hemorrhagic manifestations are epistaxis, hematuria, and menorrhagia in females, sometimes hemarthrosis even craniocerebral hemorrhage. The measurement of the FX rate in the blood allows the d...

Due to a homozygous Gly204Arg mutation in the factor X (FX) gene no detectable FX antigen was found in the plasma of a one-year old patient with severe bleeding diathesis. The amino acid replacement destabilized the disulfide bond that holds the two FX chains together, decreasing the interaction between the Cys201-Cys206 loop region and the region connecting the EGF2 and serine protease domains...

Background: Hemophilia B is an X-linked recessive coagulation disorder caused by factor IX deficiency.  Analysis of factor IX gene polymorphisms is considered the best approach for prenatal diagnosis and carrier detection of hemophilia B where the identification of gene mutation is not easily possible. Objective: To study the frequency of three factor IX-linked restriction fragment length polym...