complement factor I
Last updated 18 Aug 2020
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The CFI gene provides instructions for making a protein called complement factor I. This protein helps regulate a part of the body's immune response known as the complement system. The complement system is a group of proteins that work together to destroy foreign invaders (such as bacteria and viruses), trigger inflammation, and remove debris from cells and tissues. This system must be carefully regulated so it targets only unwanted materials and does not attack the body's healthy cells. Complement factor I and several related proteins protect healthy cells by preventing activation of the complement system when it is not needed.
Normal function
The CFI gene provides instructions for making a protein called complement factor I. This protein helps regulate a part of the body's immune response known as the complement system. The complement system is a group of proteins that work together to destroy foreign invaders (such as bacteria and viruses), trigger inflammation, and remove debris from cells and tissues. This system must be carefully regulated so it targets only unwanted materials and does not attack the body's healthy cells. Complement factor I and several related proteins protect healthy cells by preventing activation of the complement system when it is not needed.
Conditions referring to this gene or chromosome
Other names
AHUS3
C3b-INA
C3b-inactivator
C3B/C4B inactivator
C3BINA
CFAI_HUMAN
complement component I
complement control protein factor I
complement factor I heavy chain
complement factor I preproprotein
FI
IF
KAF
Konglutinogen-activating factor
light chain of factor I
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Further reading and references
- complement factor I; MedlinePlus, National Library of Medicine.
- Baracho GV, Nudelman V, Isaac L. Molecular characterization of homozygous hereditary factor I deficiency. Clin Exp Immunol. 2003 Feb;131(2):280-6. doi: 10.1046/j.1365-2249.2003.02077.x.
- Fagerness JA, Maller JB, Neale BM, Reynolds RC, Daly MJ, Seddon JM. Variation near complement factor I is associated with risk of advanced AMD. Eur J Hum Genet. 2009 Jan;17(1):100-4. doi: 10.1038/ejhg.2008.140. Epub 2008 Aug 6.
- Kavanagh D, Richards A, Noris M, Hauhart R, Liszewski MK, Karpman D, Goodship JA, Fremeaux-Bacchi V, Remuzzi G, Goodship TH, Atkinson JP. Characterization of mutations in complement factor I (CFI) associated with hemolytic uremic syndrome. Mol Immunol. 2008 Jan;45(1):95-105. doi: 10.1016/j.molimm.2007.05.004. Epub 2007 Jun 26.
- Nilsson SC, Trouw LA, Renault N, Miteva MA, Genel F, Zelazko M, Marquart H, Muller K, Sjoholm AG, Truedsson L, Villoutreix BO, Blom AM. Genetic, molecular and functional analyses of complement factor I deficiency. Eur J Immunol. 2009 Jan;39(1):310-23. doi: 10.1002/eji.200838702.
- Ponce-Castro IM, Gonzalez-Rubio C, Delgado-Cervino EM, Abarrategui-Garrido C, Fontan G, Sanchez-Corral P, Lopez-Trascasa M. Molecular characterization of Complement Factor I deficiency in two Spanish families. Mol Immunol. 2008 May;45(10):2764-71. doi: 10.1016/j.molimm.2008.02.008. Epub 2008 Mar 28.
- Richard I. The genetic and molecular bases of monogenic disorders affecting proteolytic systems. J Med Genet. 2005 Jul;42(7):529-39. doi: 10.1136/jmg.2004.028118.
- Servais A, Fremeaux-Bacchi V, Lequintrec M, Salomon R, Blouin J, Knebelmann B, Grunfeld JP, Lesavre P, Noel LH, Fakhouri F. Primary glomerulonephritis with isolated C3 deposits: a new entity which shares common genetic risk factors with haemolytic uraemic syndrome. J Med Genet. 2007 Mar;44(3):193-9. doi: 10.1136/jmg.2006.045328. Epub 2006 Oct 3.
- Vyse TJ, Morley BJ, Bartok I, Theodoridis EL, Davies KA, Webster AD, Walport MJ. The molecular basis of hereditary complement factor I deficiency. J Clin Invest. 1996 Feb 15;97(4):925-33. doi: 10.1172/JCI118515.
- Vyse TJ, Spath PJ, Davies KA, Morley BJ, Philippe P, Athanassiou P, Giles CM, Walport MJ. Hereditary complement factor I deficiency. QJM. 1994 Jul;87(7):385-401.
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