C4B

complement C4B (Chido/Rodgers blood group)

This gene encodes the basic form of complement factor 4, and together with the C4A gene, is 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 may be cleaved to release C4 anaphylatoxin, a mediator of local inflammation. Deficiency of this protein is associated with systemic lupus erythematosus. 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. In addition, this gene exists as a long form and a short form due to the presence or absence of a 6.4 kb endogenous HERV-K retrovirus in intron 9.

provided by RefSeq

Biological Domains

Autophagy, Immune Response, Synapse, Vasculature

Pharos Class

Tbio

Also known as

ENSG00000224389 (Ensembl Release 115)

UNIPROTKB P0C0L5

C4B1, C4B12, C4B2, C4B3, C4B5, C4BD, C4B_2, C4F, CH, CO4, CPAMD3

Summary of Evidence

This tab shows an overview of how the selected gene is associated with AD.

  • Genetic Association with LOAD

    Indicates whether or not this gene shows significant genetic association with Late Onset AD (LOAD) based on evidence from multiple studies compiled by the ADSP Gene Verification Committee
    False

  • Brain eQTL

    Indicates whether or not this gene locus has a significant expression Quantitative Trait Locus (eQTL) based on an AMP-AD consortium study
    True

  • RNA Expression Change in AD Brain

    Indicates whether or not this gene shows significant differential expression in at least one brain region based on AMP-AD consortium work. See ‘EVIDENCE’ tab.
    True

  • Protein Expression Change in AD Brain

    Indicates whether or not this gene shows significant differential protein expression in at least one brain region based on AMP-AD consortium work. See ‘EVIDENCE’ tab.
    True

  • Nominated Target

    Indicates whether or not this gene has been submitted as a nominated target to Agora.
    False

AD Risk Scores

About AD Risk Scores

The TREAT-AD Center at Emory-Sage-SGC has developed a Target Risk Score (TRS) to objectively rank the potential involvement of specific genes in AD. The TRS is derived by summing two component risk scores, the Genetic Risk Score and the Multi-omic Risk Score, each of which is derived from a meta-analysis of multiple harmonized data sets. More information about the methodology used to define these risk scores is available here.

AD Risk Scores for C4B

The TRS for C4B, along with the component Genetic and Multi-omic Risk Scores, is shown here. The scores for C4B are superimposed on the genome-wide score distributions. If No Data is Currently Available is displayed for a score, that score was not calculated for C4B.

Biological Domain Classification

About Biological Domains

A biological domain represents a standardized area of biology defined by a set of discrete, biologically coherent GO terms. The TREAT-AD Center at Emory-Sage-SGC has defined nineteen biological domains associated with AD, and objectively mapped genes to those biological domains using GO term annotations. More information about the methodology used to define AD biological domains, and to generate genome-wide biological domain mappings, is available here.

Biological Domains for C4B

Select a biological domain on the left to see the list of GO terms that link C4B to it on the right. The percentage value displayed next to the currently selected biological domain indicates the proportion of C4B's total unique GO terms that map to the biological domain. The ratio displayed on the right indicates how many of the biological domain's total GO terms C4B is annotated with.