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Aliases for C4A Gene

Aliases for C4A Gene

  • Complement C4A (Rodgers Blood Group) 2 3 5
  • C3 And PZP-Like Alpha-2-Macroglobulin Domain-Containing Protein 2 3 4
  • Complement Component 4A (Rodgers Blood Group) 2 3
  • Acidic Complement C4 3 4
  • CPAMD2 3 4
  • CO4 3 4
  • MHC Class III Region Complement 3
  • Complement Component 4A 2
  • Rodgers Form Of C4 3
  • C4A Anaphylatoxin 3
  • Complement C4-A 3
  • Acidic C4 3
  • C4A2 3
  • C4A3 3
  • C4A4 3
  • C4A6 3
  • C4AD 3
  • C4S 3
  • C4 3
  • RG 3

External Ids for C4A Gene

Previous GeneCards Identifiers for C4A Gene

  • GC06P032011
  • GC06Pd32003
  • GC06U900438
  • GC06P032091
  • GC06P032076
  • GC06P032092
  • GC06P031951
  • GC06P031952
  • GC06P031954
  • GC06P031993
  • GC06P031984
  • GC06P031989
  • GC06P032045

Summaries for C4A Gene

Entrez Gene Summary for C4A Gene

  • 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]

GeneCards Summary for C4A Gene

C4A (Complement C4A (Rodgers Blood Group)) is a Protein Coding gene. Diseases associated with C4A include Complement Component 4A Deficiency and Blood Group, Chido/Rodgers System. Among its related pathways are Sudden Infant Death Syndrome (SIDS) Susceptibility Pathways and Complement and coagulation cascades. Gene Ontology (GO) annotations related to this gene include endopeptidase inhibitor activity and complement component C1q binding. An important paralog of this gene is C4B.

UniProtKB/Swiss-Prot for C4A Gene

  • Non-enzymatic component of C3 and C5 convertases and thus essential for the propagation of the classical complement pathway. Covalently binds to immunoglobulins and immune complexes and enhances the solubilization of immune aggregates and the clearance of IC through CR1 on erythrocytes. C4A isotype is responsible for effective binding to form amide bonds with immune aggregates or protein antigens, while C4B isotype catalyzes the transacylation of the thioester carbonyl group to form ester bonds with carbohydrate antigens.

  • Derived from proteolytic degradation of complement C4, C4a anaphylatoxin is a mediator of local inflammatory process. It induces the contraction of smooth muscle, increases vascular permeability and causes histamine release from mast cells and basophilic leukocytes.

Gene Wiki entry for C4A Gene

Additional gene information for C4A Gene

No data available for CIViC summary , Tocris Summary , PharmGKB "VIP" Summary , fRNAdb sequence ontologies and piRNA Summary for C4A Gene

Genomics for C4A Gene

GeneHancer (GH) Regulatory Elements for C4A Gene

Promoters and enhancers for C4A Gene
GeneHancer (GH) Identifier GH Type GH
GH Sources Gene Association Score Total Score TSS distance (kb) Number of Genes Away Size (kb) Transcription Factor
Binding Sites
Gene Targets
GH06J031981 Promoter/Enhancer 0.7 EPDnew Ensembl 650.7 +0.1 77 0.6 C4A STK19 C4A-AS1
GH06J031980 Promoter/Enhancer 0.7 EPDnew dbSUPER 650.7 -1.3 -1344 0.1 C4A PIR57560 STK19
GH06J032106 Promoter/Enhancer 2 EPDnew FANTOM5 Ensembl ENCODE dbSUPER 33.8 +129.2 129228 9.7 PKNOX1 GATA2 E2F8 ARID2 ZNF143 FOS ZNF263 SP3 RXRA REST TNXB ATF6B C4A SKIV2L BRD2 LY6G5B DDX39B HLA-DRB1 LSM2 STK19
GH06J031792 Promoter/Enhancer 2.7 EPDnew FANTOM5 Ensembl ENCODE dbSUPER 20.3 -186.3 -186329 6.7 DMAP1 YY1 ZNF213 E2F8 ZNF143 SP3 NFYC MEF2D SSRP1 ZNF610 VARS ATF6B LSM2 BAG6 LY6G5B MSH5 SKIV2L GPANK1 DDX39B PRRC2A
GH06J031733 Promoter/Enhancer 2.7 EPDnew FANTOM5 Ensembl ENCODE dbSUPER 20.1 -244.6 -244569 8.5 CLOCK MLX ZFP64 YBX1 FEZF1 DMAP1 IRF4 YY1 SLC30A9 ZNF213 MSH5 CLIC1 MSH5-SAPCD1 DDX39B LY6G5B ATF6B LSM2 SKIV2L CSNK2B GPANK1
- Elite GeneHancer and/or Elite GeneHancer-gene association Download GeneHancer data from 2017 publication | Request up-to-date GeneHancer data (full dataset)

GeneHancers around C4A on UCSC Golden Path with GeneCards custom track

Top Transcription factor binding sites by QIAGEN in the C4A gene promoter:
  • STAT1alpha
  • Pax-5
  • NF-kappaB
  • NF-kappaB1
  • STAT1
  • STAT1beta
  • RFX1
  • Pax-4a
  • Max
  • c-Myc

Genomic Locations for C4A Gene

Genomic Locations for C4A Gene
20,658 bases
Plus strand
20,658 bases
Plus strand

Genomic View for C4A Gene

Genes around C4A on UCSC Golden Path with GeneCards custom track

Cytogenetic band:
C4A Gene in genomic location: bands according to Ensembl, locations according to GeneLoc (and/or Entrez Gene and/or Ensembl if different)
Genomic Location for C4A Gene
GeneLoc Logo Genomic Neighborhood Exon StructureGene Density

RefSeq DNA sequence for C4A Gene

Proteins for C4A Gene

  • Protein details for C4A Gene (UniProtKB/Swiss-Prot)

    Protein Symbol:
    Recommended name:
    Complement C4-A
    Protein Accession:
    Secondary Accessions:
    • A6H8M8
    • A6NHJ5
    • A7E2V2
    • B0QZR6
    • B0V2C8
    • B2RUT6
    • B7ZVZ6
    • P01028
    • P78445
    • Q13160
    • Q13906
    • Q14033
    • Q14835
    • Q4LE82
    • Q5JNX2
    • Q5JQM8
    • Q6P4R1
    • Q6U2E5
    • Q6U2E8
    • Q6U2F0
    • Q6U2F3
    • Q6U2F4
    • Q6U2F6
    • Q6U2F8
    • Q6U2G0
    • Q96EG2
    • Q96SA8
    • Q9NPK5
    • Q9UIP5

    Protein attributes for C4A Gene

    1744 amino acids
    Molecular mass:
    192785 Da
    Quaternary structure:
    • Circulates in blood as a disulfide-linked trimer of an alpha, beta and gamma chain.
    • Sequence=AAB59537.1; Type=Miscellaneous discrepancy; Note=During cDNA synthesis, the 5 end has been inverted (PubMed:3838531).; Evidence={ECO:0000305 PubMed:3838531}; Sequence=BAE06071.1; Type=Erroneous initiation; Note=Translation N-terminally shortened.; Evidence={ECO:0000305};

    Three dimensional structures from OCA and Proteopedia for C4A Gene

    Alternative splice isoforms for C4A Gene


neXtProt entry for C4A Gene

Post-translational modifications for C4A Gene

  • Prior to secretion, the single-chain precursor is enzymatically cleaved to yield non-identical chains alpha, beta and gamma. During activation, the alpha chain is cleaved by C1 into C4a and C4b, and C4b stays linked to the beta and gamma chains. Further degradation of C4b by C1 into the inactive fragments C4c and C4d blocks the generation of C3 convertase. The proteolytic cleavages often are incomplete so that many structural forms can be found in plasma.
  • N- and O-glycosylated. O-glycosylated with a core 1 or possibly core 8 glycan.
  • Glycosylation at Asn1391, posLast=13281328, posLast=12441244, posLast=862862, and posLast=226226
  • Modification sites at PhosphoSitePlus
  • Glycosylation from GlyConnect
    • CO4A_HUMAN (651)

Other Protein References for C4A Gene

ENSEMBL proteins:
REFSEQ proteins:

Antibody Products

No data available for DME Specific Peptides for C4A Gene

Domains & Families for C4A Gene

Gene Families for C4A Gene

Human Protein Atlas (HPA):
  • Blood group antigen proteins
  • Disease related genes
  • FDA approved drug targets
  • Plasma proteins
  • Predicted secreted proteins

Graphical View of Domain Structure for InterPro Entry

genes like me logo Genes that share domains with C4A: view

No data available for UniProtKB/Swiss-Prot for C4A Gene

Function for C4A Gene

Molecular function for C4A Gene

UniProtKB/Swiss-Prot Function:
Non-enzymatic component of C3 and C5 convertases and thus essential for the propagation of the classical complement pathway. Covalently binds to immunoglobulins and immune complexes and enhances the solubilization of immune aggregates and the clearance of IC through CR1 on erythrocytes. C4A isotype is responsible for effective binding to form amide bonds with immune aggregates or protein antigens, while C4B isotype catalyzes the transacylation of the thioester carbonyl group to form ester bonds with carbohydrate antigens.
UniProtKB/Swiss-Prot Function:
Derived from proteolytic degradation of complement C4, C4a anaphylatoxin is a mediator of local inflammatory process. It induces the contraction of smooth muscle, increases vascular permeability and causes histamine release from mast cells and basophilic leukocytes.
GENATLAS Biochemistry:
complement component 4A,primarily expressed in liver and to a lesser extent in immune cells,including the ZA transcript,embedded in intron 35 and overlapping exon 36 (?and others) in the same orientation,expressed specifically in adrenals,under the control of a putative promoter,embedded in intron 35 and containing a potential binding site for steroidogenic factor 1

Phenotypes From GWAS Catalog for C4A Gene

Gene Ontology (GO) - Molecular Function for C4A Gene

GO ID Qualified GO term Evidence PubMed IDs
GO:0001849 complement component C1q binding IDA 2395880
GO:0004252 serine-type endopeptidase activity TAS --
GO:0004866 endopeptidase inhibitor activity IEA --
GO:0005515 protein binding IEA --
genes like me logo Genes that share ontologies with C4A: view
genes like me logo Genes that share phenotypes with C4A: view

Human Phenotype Ontology for C4A Gene

HPO Id HPO Name Alternative Ids Definition Synonyms

Clone Products

No data available for Enzyme Numbers (IUBMB) , Animal Models , miRNA , Transcription Factor Targets and HOMER Transcription for C4A Gene

Localization for C4A Gene

Subcellular locations from UniProtKB/Swiss-Prot for C4A Gene

Secreted. Cell junction, synapse. Cell projection, axon. Cell projection, dendrite.

Subcellular locations from

Extracellular space Cytosol Plasma membrane Cytoskeleton Lysosome Endosome Peroxisome ER Golgi Apparatus Nucleus Mitochondrion 0 1 2 3 4 5 Confidence
COMPARTMENTS Subcellular localization image for C4A gene
Compartment Confidence
plasma membrane 5
extracellular 5
endoplasmic reticulum 4
mitochondrion 2
nucleus 2
cytosol 2
lysosome 1

Gene Ontology (GO) - Cellular Components for C4A Gene

GO ID Qualified GO term Evidence PubMed IDs
GO:0005576 extracellular region TAS --
GO:0005615 extracellular space IDA 25645918
GO:0005788 endoplasmic reticulum lumen TAS --
GO:0005886 plasma membrane TAS --
GO:0030054 cell junction IEA --
genes like me logo Genes that share ontologies with C4A: view

No data available for Subcellular locations from the Human Protein Atlas (HPA) for C4A Gene

Pathways & Interactions for C4A Gene

genes like me logo Genes that share pathways with C4A: view

Gene Ontology (GO) - Biological Process for C4A Gene

GO ID Qualified GO term Evidence PubMed IDs
GO:0002376 immune system process IEA --
GO:0006508 proteolysis IEA --
GO:0006954 inflammatory response IEA --
GO:0006956 complement activation TAS,IGI --
GO:0006958 complement activation, classical pathway IEA --
genes like me logo Genes that share ontologies with C4A: view

No data available for SIGNOR curated interactions for C4A Gene

Drugs & Compounds for C4A Gene

(5) Drugs for C4A Gene - From: DrugBank and Novoseek

Name Status Disease Links Group Role Mechanism of Action Clinical Trials
Immune Globulin Human Approved, Investigational Pharma Target, binder 0

(7) Additional Compounds for C4A Gene - From: Novoseek

Name Synonyms Role CAS Number PubChem IDs PubMed IDs
genes like me logo Genes that share compounds with C4A: view

Transcripts for C4A Gene

mRNA/cDNA for C4A Gene

(2) REFSEQ mRNAs :
(15) Additional mRNA sequences :
(17) Ensembl transcripts including schematic representations, and UCSC links where relevant :

Unigene Clusters for C4A Gene

Complement component 4A (Rodgers blood group):
Representative Sequences:

Clone Products

Alternative Splicing Database (ASD) splice patterns (SP) for C4A Gene

No ASD Table

Relevant External Links for C4A Gene

GeneLoc Exon Structure for
ECgene alternative splicing isoforms for

Expression for C4A Gene

mRNA expression in normal human tissues from GTEx, Illumina, BioGPS, and CGAP SAGE for C4A Gene

mRNA expression in embryonic tissues and stem cells from LifeMap Discovery

mRNA differential expression in normal tissues according to GTEx for C4A Gene

This gene is overexpressed in Liver (x18.2) and Adrenal Gland (x5.0).

Protein differential expression in normal tissues from HIPED for C4A Gene

This gene is overexpressed in Plasma (21.2), Serum (17.2), and Vitreous humor (12.7).

Integrated Proteomics: protein expression in normal tissues and cell lines from ProteomicsDB, MaxQB, and MOPED for C4A Gene

NURSA nuclear receptor signaling pathways regulating expression of C4A Gene:


SOURCE GeneReport for Unigene cluster for C4A Gene:


mRNA Expression by UniProt/SwissProt for C4A Gene:

Tissue specificity: Complement component C4 is expressed at highest levels in the liver, at moderate levels in the adrenal cortex, adrenal medulla, thyroid gland,and the kidney, and at lowest levels in the heart, ovary, small intestine, thymus, pancreas and spleen. The extra-hepatic sites of expression may be important for the local protection and inflammatory response.

Evidence on tissue expression from TISSUES for C4A Gene

  • Liver(4.9)
  • Nervous system(4.8)
  • Bone marrow(4.1)
  • Blood(3)
  • Eye(2.8)
  • Adrenal gland(2.5)
  • Heart(2.5)
  • Kidney(2.4)
  • Lung(2.4)
  • Gall bladder(2.3)
  • Intestine(2)
  • Pancreas(2)

Phenotype-based relationships between genes and organs from Gene ORGANizer for C4A Gene

Germ Layers:
  • ectoderm
  • endoderm
  • mesoderm
  • cardiovascular
  • digestive
  • endocrine
  • immune
  • integumentary
  • lymphatic
  • nervous
  • reproductive
  • respiratory
  • skeletal muscle
  • skeleton
  • urinary
Head and neck:
  • brain
  • cheek
  • cranial nerve
  • ear
  • eye
  • face
  • head
  • lip
  • meninges
  • mouth
  • neck
  • scalp
  • thyroid
  • bronchus
  • esophagus
  • heart
  • lung
  • intestine
  • kidney
  • large intestine
  • liver
  • pancreas
  • small intestine
  • spleen
  • stomach
  • penis
  • testicle
  • vagina
  • ankle
  • digit
  • elbow
  • finger
  • foot
  • hand
  • hip
  • knee
  • lower limb
  • shoulder
  • toe
  • upper limb
  • wrist
  • blood
  • blood vessel
  • bone marrow
  • coagulation system
  • hair
  • lymph node
  • peripheral nerve
  • peripheral nervous system
  • skin
  • spinal cord
  • white blood cell
genes like me logo Genes that share expression patterns with C4A: view

No data available for Protein tissue co-expression partners for C4A Gene

Orthologs for C4A Gene

This gene was present in the common ancestor of chordates.

Orthologs for C4A Gene

Organism Taxonomy Gene Similarity Type Details
(Pan troglodytes)
Mammalia C4A 33
  • 99.33 (n)
-- 34
  • 99 (a)
-- 34
  • 99 (a)
(Canis familiaris)
Mammalia C4A 33
  • 83.97 (n)
-- 34
  • 82 (a)
(Bos Taurus)
Mammalia C4A 33
  • 83.71 (n)
-- 34
  • 80 (a)
-- 34
  • 75 (a)
(Rattus norvegicus)
Mammalia C4a 33
  • 80.8 (n)
(Mus musculus)
Mammalia C4b 34 33
  • 79.01 (n)
(Monodelphis domestica)
Mammalia -- 34
  • 67 (a)
(Ornithorhynchus anatinus)
Mammalia -- 34
  • 66 (a)
(Gallus gallus)
Aves C4 34 33
  • 51.99 (n)
(Anolis carolinensis)
Reptilia -- 34
  • 44 (a)
tropical clawed frog
(Silurana tropicalis)
Amphibia c4a 33
  • 49.53 (n)
(Danio rerio)
Actinopterygii si:dkey-8k3.2 34 33
  • 46.95 (n)
sea squirt
(Ciona savignyi)
Ascidiacea CSA.4097 34
  • 22 (a)
-- 34
  • 21 (a)
Species where no ortholog for C4A was found in the sources mined by GeneCards:
  • A. gosspyii yeast (Ashbya gossypii)
  • Actinobacteria (Mycobacterium tuberculosis)
  • African clawed frog (Xenopus laevis)
  • African malaria mosquito (Anopheles gambiae)
  • Alicante grape (Vitis vinifera)
  • alpha proteobacteria (Wolbachia pipientis)
  • amoeba (Dictyostelium discoideum)
  • Archea (Pyrococcus horikoshii)
  • baker's yeast (Saccharomyces cerevisiae)
  • barley (Hordeum vulgare)
  • beta proteobacteria (Neisseria meningitidis)
  • bread mold (Neurospora crassa)
  • Chromalveolata (Phytophthora infestans)
  • common water flea (Daphnia pulex)
  • corn (Zea mays)
  • E. coli (Escherichia coli)
  • filamentous fungi (Aspergillus nidulans)
  • Firmicute bacteria (Streptococcus pneumoniae)
  • fission yeast (Schizosaccharomyces pombe)
  • fruit fly (Drosophila melanogaster)
  • green algae (Chlamydomonas reinhardtii)
  • honey bee (Apis mellifera)
  • K. lactis yeast (Kluyveromyces lactis)
  • loblloly pine (Pinus taeda)
  • malaria parasite (Plasmodium falciparum)
  • medicago trunc (Medicago Truncatula)
  • moss (Physcomitrella patens)
  • orangutan (Pongo pygmaeus)
  • pig (Sus scrofa)
  • rainbow trout (Oncorhynchus mykiss)
  • rice (Oryza sativa)
  • rice blast fungus (Magnaporthe grisea)
  • schistosome parasite (Schistosoma mansoni)
  • sea anemone (Nematostella vectensis)
  • sea urchin (Strongylocentrotus purpuratus)
  • sorghum (Sorghum bicolor)
  • soybean (Glycine max)
  • stem rust fungus (Puccinia graminis)
  • sugarcane (Saccharum officinarum)
  • thale cress (Arabidopsis thaliana)
  • tomato (Lycopersicon esculentum)
  • toxoplasmosis (Toxoplasma gondii)
  • Trichoplax (Trichoplax adhaerens)
  • wheat (Triticum aestivum)
  • worm (Caenorhabditis elegans)

Evolution for C4A Gene

Gene Tree for C4A (if available)
Gene Tree for C4A (if available)
Evolutionary constrained regions (ECRs) for C4A: view image

Paralogs for C4A Gene

Paralogs for C4A Gene

(6) SIMAP similar genes for C4A Gene using alignment to 5 proteins:

  • F5H2J9_HUMAN
  • Q30211_HUMAN
  • Q6U2K2_HUMAN
  • V9H0D6_HUMAN
genes like me logo Genes that share paralogs with C4A: view

Variants for C4A Gene

Polymorphic Variants from UniProtKB/Swiss-Prot for C4A Gene

The complement component C4 is the most polymorphic protein of the complement system. It is the product of 2 closely linked and highly homologous genes, C4A and C4B. Once polymorphic variation is discounted, the 2 isotypes differ by only 4 amino acids at positions 1120-1125: PCPVLD for C4A and LSPVIH for C4B. The 2 isotypes bear several antigenic determinants defining Chido/Rodgers blood group system [MIM:614374]. Rodgers determinants are generally associated with C4A allotypes, and Chido with C4B. Variations at these loci involve not only nucleotide polymorphisms, but also gene number and gene size. Some individuals may lack either C4A, or C4B gene. Partial deficiency of C4A or C4B is the most commonly inherited immune deficiency known in humans with a combined frequency over 31% in the normal Caucasian population (PubMed:11367523). C4A6 allotype is deficient in hemolytic activity. Allotype C4A13 is infrequent. Common copy-number variants of C4A and C4B affecting expression of complement component C4 in the brain have been associated with schizophrenia risk (PubMed:26814963).

Sequence variations from dbSNP and Humsavar for C4A Gene

SNP ID Clin Chr 06 pos Variation AA Info Type
rs1000726010 -- 31,995,990(+) C/T coding_sequence_variant, missense_variant
rs1001158549 -- 31,980,963(+) G/A upstream_transcript_variant
rs1001324282 -- 31,998,009(+) C/A intron_variant
rs1002089632 -- 31,996,854(+) T/C coding_sequence_variant, synonymous_variant
rs1004522192 -- 31,996,675(+) A/C intron_variant

Structural Variations from Database of Genomic Variants (DGV) for C4A Gene

Variant ID Type Subtype PubMed ID
dgv10403n54 CNV loss 21841781
dgv10404n54 CNV loss 21841781
dgv10463n54 CNV loss 21841781
dgv10466n54 CNV loss 21841781
dgv10467n54 CNV loss 21841781
dgv10468n54 CNV loss 21841781
dgv10469n54 CNV loss 21841781
dgv10470n54 CNV loss 21841781
dgv10471n54 CNV loss 21841781
dgv10472n54 CNV loss 21841781
dgv10473n54 CNV loss 21841781
dgv10474n54 CNV gain 21841781
dgv10475n54 CNV loss 21841781
dgv20n31 CNV gain 19718026
dgv3474e59 CNV duplication 20981092
esv2759415 CNV gain+loss 17122850
esv28110 CNV gain+loss 19812545
esv32938 CNV gain 17666407
esv3333985 CNV duplication 20981092
esv3340418 CNV duplication 20981092
esv3431334 CNV duplication 20981092
esv3890824 CNV loss 25118596
esv3890825 CNV loss 25118596
esv3890827 CNV gain+loss 25118596
esv3890828 CNV loss 25118596
nsv1073969 CNV deletion 25765185
nsv10824 CNV gain+loss 18304495
nsv1112900 CNV deletion 24896259
nsv1126749 CNV deletion 24896259
nsv284 CNV deletion 15895083
nsv428141 CNV gain+loss 18775914
nsv515035 CNV gain+loss 21397061
nsv5247 CNV deletion 18451855
nsv601971 CNV gain 21841781
nsv601988 CNV gain 21841781
nsv601990 CNV loss 21841781
nsv601991 CNV loss 21841781
nsv602004 CNV gain+loss 21841781
nsv602030 CNV loss 21841781
nsv602034 CNV loss 21841781
nsv602038 CNV loss 21841781
nsv602041 CNV loss 21841781
nsv602045 CNV gain 21841781
nsv602050 CNV loss 21841781
nsv819957 CNV loss 19587683
nsv821566 CNV deletion 20802225
nsv823506 CNV loss 20364138
nsv823507 CNV loss 20364138
nsv981129 CNV duplication 23825009

Variation tolerance for C4A Gene

Gene Damage Index Score: 1.32; 26.24% of all genes are more intolerant (likely to be disease-causing)

Additional Variant Information for C4A Gene

Human Gene Mutation Database (HGMD)
Blood Group Antigen Gene Mutation Database (BGMUT)
Blood Group System
SNPedia medical, phenotypic, and genealogical associations of SNPs for

SNP Genotyping and Copy Number Assay Products

Disorders for C4A Gene

MalaCards: The human disease database

(35) MalaCards diseases for C4A Gene - From: HGMD, OMIM, ClinVar, Orphanet, DISEASES, Novoseek, and GeneCards

Disorder Aliases PubMed IDs
complement component 4a deficiency
  • c4ad
blood group, chido/rodgers system
  • chido/rodgers blood group system
immunodeficiency due to a classical component pathway complement deficiency
  • immunodeficiency due to c1, c4, or c2 component complement deficiency
lupus erythematosus
  • systemic lupus erythematosus
felty syndrome
  • felty's syndrome
- elite association - COSMIC cancer census association via MalaCards
Search C4A in MalaCards View complete list of genes associated with diseases


  • Complement component 4A deficiency (C4AD) [MIM:614380]: A rare defect of the complement classical pathway associated with the development of autoimmune disorders, mainly systemic lupus with or without associated glomerulonephritis. {ECO:0000269 PubMed:8473511}. Note=The disease is caused by mutations affecting the gene represented in this entry.
  • Systemic lupus erythematosus (SLE) [MIM:152700]: A chronic, relapsing, inflammatory, and often febrile multisystemic disorder of connective tissue, characterized principally by involvement of the skin, joints, kidneys and serosal membranes. It is of unknown etiology, but is thought to represent a failure of the regulatory mechanisms of the autoimmune system. The disease is marked by a wide range of system dysfunctions, an elevated erythrocyte sedimentation rate, and the formation of LE cells in the blood or bone marrow. {ECO:0000269 PubMed:10092831, ECO:0000269 PubMed:17503323}. Note=Disease susceptibility is associated with variations affecting the gene represented in this entry. Interindividual copy-number variation (CNV) of complement component C4 and associated polymorphisms result in different susceptibilities to SLE. The risk of SLE susceptibility has been shown to be significantly increased among subjects with only two copies of total C4. A high copy number is a protective factor against SLE.

Additional Disease Information for C4A

Genetic Association Database
Human Genome Epidemiology Navigator
ATLAS of Genetics and Cytogenetics in Oncology and Haematology
genes like me logo Genes that share disorders with C4A: view

No data available for Genatlas for C4A Gene

Publications for C4A Gene

  1. High-throughput analysis of the C4 polymorphism by a combination of MLPA and isotype-specific ELISA's. (PMID: 19062096) Wouters D … Hamann D (Molecular immunology 2009) 3 22 44 58
  2. Complement 4 phenotypes and genotypes in Brazilian patients with classical 21-hydroxylase deficiency. (PMID: 19137635) Guerra-Junior G … De Mello MP (Clinical and experimental immunology 2009) 3 22 44 58
  3. Polymerase chain reaction based C4AQ0 and C4BQ0 genotyping: association with systemic lupus erythematosus in southwest Han Chinese. (PMID: 12480675) Man XY … Zhang YP (Annals of the rheumatic diseases 2003) 3 22 44 58
  4. Lack of evidence of a specific role for C4A gene deficiency in determining disease susceptibility among C4-deficient patients with systemic lupus erythematosus (SLE). (PMID: 11168010) Dragon-Durey MA … Weiss L (Clinical and experimental immunology 2001) 3 22 44 58
  5. Genetic, structural and functional diversities of human complement components C4A and C4B and their mouse homologues, Slp and C4. (PMID: 11367523) Blanchong CA … Yu CY (International immunopharmacology 2001) 3 4 22 58

Products for C4A Gene

Sources for C4A Gene