Factor IX - Christmas Factor

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Factor IX, also known as Christmas factor, is a clotting protein that's involved in blood coagulation. It's a serine protease in the coagulation system.

The role of Christmas factor is to cleave a peptide bond in another enzyme, Factor X.

Factor IX deficiency is also known as: Christmas disease, Hemophilia B, FIX deficiency.

Factor IX deficiency is a genetic disorder that can be caused by:

• Missing or defective factor IX
• A spontaneous mutation

The disorder was named after Stephen Christmas, the first person to be diagnosed with the disorder in 1952.