Factor XII - Hageman factor

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Factor XII, also known as Hageman factor, is a plasma protein that helps blood clot after an injury. It's a protease that's produced in the liver and circulates in plasma. When Factor XII comes into contact with a damaged vein wall, it activates coagulation factor XI.

Factor XII deficiency is a rare genetic disorder that causes prolonged blood clotting. It's estimated to affect 1 in a million people. The condition was first identified in 1955 in John Hageman.

Factor XII deficiency is caused by a deficiency of Factor XII, which is a glycoprotein. It's an inherited condition that's usually passed on in an autosomal recessive manner.

Factor XII is activated by negatively charged substances, such as:

Polyphosphates, Nucleic acids, Heparin, Collagen, Misfolded proteins, Extracellular traps, Anionic bacterial surfaces