Factor IX

Title: Factor IX
CAS Registry Number: 9001-28-9
CAS Name: Blood-coagulation factor IX
Additional Names: Christmas factor; PTC; plasma thromboplastin component; antihemophilic factor B; autoprothrombin II
Literature References: A plasma and serum glycoprotein that participates in the middle phases of blood coagulation. Activated by factor XI and Ca2+. Interacts then with factor VIII, Ca2+, and phospholipid to form the complex which converts factor X into factor Xa. Isoln and characterization of bovine factor IX: K. Fujikawa et al., Biochemistry 12, 4938 (1973); K. Fujikawa, E. W. Davie, Methods Enzymol. 45B, 74 (1976). Deficiency results in a congenital bleeding disorder known as Christmas disease or hemophilia B. Review: Macfarlane in Thrombolytic Activity and Related Phenomena, I. S. Wright et al., Eds. (Schattauer-Verlag, Stuttgart, 1961) pp 408-415; B. N. Bouma, J. A. Van Mourik, Haemostasis: Biochemistry, Physiology & Pathology, D. Ogston, B. Bennett, Eds. (Wiley-Interscience, New York, 1977) pp 56-77.
Derivative Type: Factor IX complex (human)
Trademarks: Konyne (Miles); Profilnine (Alpha Ther.); Proplex T (Baxter)
Properties: A mixture of human factors II, VII, IX, and X.
Derivative Type: Factor IX (human)
Trademarks: AlphaNine (Alpha Ther.); Mononine (ZLB Behring)
Therap-Cat: Hemostatic.
Keywords: Hemostatic.
Factor V Factor VII Factor VIII Factor X Factor XI

Coagulation factor IX

PDB rendering based on 1pfx.
Available structures
PDB Ortholog search: PDBe, RCSB
Symbols F9 (; FIX; HEMB; P19; PTC; THPH8)
External IDs OMIM: 300746 MGI: 88384 HomoloGene: 106 ChEMBL: 2016 GeneCards: F9 Gene
EC number
RNA expression pattern
PBB GE F9 207218 at tn.png
More reference expression data
Species Human Mouse
Entrez 2158 14071
Ensembl ENSG00000101981 ENSMUSG00000031138
UniProt P00740 P16294
RefSeq (mRNA) NM_000133 NM_007979
RefSeq (protein) NP_000124 NP_032005
Location (UCSC) Chr X:
138.61 – 138.65 Mb
Chr X:
60 – 60.03 Mb
PubMed search [1] [2]

Factor IX (or Christmas factor) (EC is one of the serine proteases of the coagulation system; it belongs to peptidase family S1. Deficiency of this protein causes hemophilia B. It was discovered in 1952 after a young boy named Stephen Christmas was found to be lacking this exact factor, leading to hemophilia.[1]