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Published on: September 9, 2012
Molecular Analysis in Factor XI Deficiency
1Haemostasis Research Group, MRC Clinical Sciences Centre, Royal Postgraduate Medical School, Hammersmith Hospital, London, UK.
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Factor XI (FXI) is the zymogen precursor of an active serine protease that participates in the contact phase of coagulation. Synthesized in the liver, it circulates in the plasma in a noncovalent complex with high molecular weight kininogen (1) at a normal concentration of 5 microg/mL. (For clinical purposes, the normal range is defined as 50-150 U/dL) (2). FXI circulates as a homodimeric glycoprotein with a mass of 160 kDa.
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