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Medical Term:

factor XII


in the clotting of blood, also known as glass factor and Hageman factor When activated by glass or otherwise to its active form, factor XIIa (EC, a serine proteinase, it activates factors VII and XI and converts factor XI to its active form, factor XIa. Deficiency of factor XII results in great prolongation of the clotting time of venous blood, but only rarely in a hemorrhagic tendency; deficiency is caused by an autosomal recessive gene.

Synonym(s): glass factor, Hageman factor

© Copyright 2017 Wolters Kluwer. All Rights Reserved. Review Date: Sep 19, 2016.