What is the official name of the C5 gene?
The official name of this gene is “complement component 5.”
C5 is the gene's official symbol. The C5 gene is also known by other names, listed below.
Read more about gene names and symbols on the About page.
What is the normal function of the C5 gene?
- From NCBI Gene:
The protein encoded by this gene is the fifth component of complement, which plays an important role in inflammatory and cell killing processes. This protein is comprised of alpha and beta polypeptide chains that are linked by a disulfide bridge. An activation peptide, C5a, which is an anaphylatoxin that possesses potent spasmogenic and chemotactic activity, is derived from the alpha polypeptide via cleavage with a convertase. The C5b macromolecular cleavage product can form a complex with the C6 complement component, and this complex is the basis for formation of the membrane attack complex, which includes additional complement components. Mutations in this gene cause complement component 5 deficiency, a disease where patients show a propensity for severe recurrent infections. Defects in this gene have also been linked to a susceptibility to liver fibrosis and to rheumatoid arthritis. [provided by RefSeq, Jul 2008]
- From UniProt:
Activation of C5 by a C5 convertase initiates the spontaneous assembly of the late complement components, C5-C9, into the membrane attack complex. C5b has a transient binding site for C6. The C5b-C6 complex is the foundation upon which the lytic complex is assembled.Derived from proteolytic degradation of complement C5, C5 anaphylatoxin is a mediator of local inflammatory process. Binding to the receptor C5AR1 induces a variety of responses including intracellular calcium release, contraction of smooth muscle, increased vascular permeability, and histamine release from mast cells and basophilic leukocytes (PubMed:8182049). C5a is also a potent chemokine which stimulates the locomotion of polymorphonuclear leukocytes and directs their migration toward sites of inflammation.
How are changes in the C5 gene related to health conditions?
- Genetics Home Reference provides information about rheumatoid arthritis, which is associated with changes in the C5 gene.
- UniProt provides the following information about the C5 gene's known or predicted involvement in human disease.
Complement component 5 deficiency (C5D): A rare defect of the complement classical pathway associated with susceptibility to severe recurrent infections, predominantly by Neisseria gonorrhoeae or Neisseria meningitidis. The disease is caused by mutations affecting the gene represented in this entry.
An association study of C5 haplotypes and genotypes in individuals with chronic hepatitis C virus infection shows that individuals homozygous for the C5_1 haplotype have a significantly higher stage of liver fibrosis than individuals carrying at least 1 other allele.
- NCBI Gene lists the following diseases or traits (phenotypes) known or believed to be associated with changes in the C5 gene.
- Eculizumab, poor response to
- Leiner disease
- OMIM.org, a catalog designed for genetics professionals and researchers, provides the following information about the C5 gene and its association with health conditions.
Where is the C5 gene located?
Cytogenetic Location: 9q33-q34
Molecular Location on chromosome 9: base pairs 120,952,334 to 121,050,275
The C5 gene is located on the long (q) arm of chromosome 9 between positions 33 and 34.
More precisely, the C5 gene is located from base pair 120,952,334 to base pair 121,050,275 on chromosome 9.
See How do geneticists indicate the location of a gene? in the Handbook.
Where can I find additional information about C5?
You and your healthcare professional may find the following resources about C5 helpful.
- Genetic Testing Registry - Repository of genetic test information
You may also be interested in these resources, which are designed for genetics professionals and researchers.
- OMIM - Genetic disorder catalog
- Research Resources - Tools for researchers
What other names do people use for the C5 gene or gene products?
Where can I find general information about genes?
The Handbook provides basic information about genetics in clear language.
These links provide additional genetics resources that may be useful.
What glossary definitions help with understanding C5?
The resources on this site should not be used as a substitute for
professional medical care or advice. Users seeking information about
a personal genetic disease, syndrome, or condition should consult with a qualified
See How can I find a genetics professional in my area? in the Handbook.