LongevityMap variant
- Longevity Association
- Non-significant
- Population
- Italian
- Study Design
- C4 alleles were examined in healthy aged people (77 centenarians and 89 elderly subjects)
- Conclusions
- The frequencies of C4A alleles were similar in the studied cohorts. For C4B null allele (C4BQ0) a trend toward an increase in the older cohort was observed, although the differences were not statistically significant after correction for multiple testing.
- HGNC symbol
- C4A
- Aliases
- C4; RG; C4S; CO4; C4A2; C4A3; C4A4; C4A6; C4AD; CPAMD2
- Common name
- complement C4A (Rodgers blood group)
- Description
- This gene encodes the acidic form of complement factor 4, part of the classical activation pathway. The protein is expressed as a single chain precursor which is proteolytically cleaved into a trimer of alpha, beta, and gamma chains prior to secretion. The trimer provides a surface for interaction between the antigen-antibody complex and other complement components. The alpha chain is cleaved to release C4 anaphylatoxin, an antimicrobial peptide and a mediator of local inflammation. Deficiency of this protein is associated with systemic lupus erythematosus and type I diabetes mellitus. This gene localizes to the major histocompatibility complex (MHC) class III region on chromosome 6. Varying haplotypes of this gene cluster exist, such that individuals may have 1, 2, or 3 copies of this gene. Two transcript variants encoding different isoforms have been found for this gene. [provided by RefSeq, Nov 2014]
- OMIM
- 120810
- Ensembl
- ENSG00000244731
- UniProt/Swiss-Prot
- CO4A_HUMAN
- Entrez Gene
- 720
- UniGene
- 534847
- HapMap
- View on HapMap
Homologs in model organisms
- Danio rerio
- c4
- Drosophila melanogaster
- Tep5
- Drosophila melanogaster
- Mcr
- Drosophila melanogaster
- Tep1
- Drosophila melanogaster
- Tep4
- Drosophila melanogaster
- Tep3
- Drosophila melanogaster
- Tep2
- Mus musculus
- C4b
- Rattus norvegicus
- C4a
- Rattus norvegicus
- C4b
- Rattus norvegicus
- C4a
Bellavia et al. (1999)
Other variants which are also part of this study