C9

Chr 5p13.1

complement C9

MANE:: ENST00000263408.5

OMIM: 120940 ↗NCBI: 735 ↗Ensembl ↗

Annotations refreshed 9 hours ago.

Predicted protein structure

AlphaFold predicted structure

C9 · P02748

v62025-08-01

Predicted Aligned Error matrix for C9 — diagonal shows residue index, colour shows pairwise prediction confidence (lower is better) — Predicted Aligned Error

Mean pLDDT

78.8/ 100

Confident

559 residues

Confidence breakdown

Very high(≥ 90)39%
Confident(70–90)39%
Low(50–70)7%
Very low(< 50)16%

Open interactive 3D viewer

AlphaFold (Jumper et al., 2021) · CC BY 4.0

Clinical relevance (Genomics England PanelApp)

Diagnostic Grade (Green)

COVID-19 research
BIALLELIC, autosomal or pseudoautosomal
Primary immunodeficiency or monogenic inflammatory bowel disease
BIALLELIC, autosomal or pseudoautosomal

Disease associations (Open Targets)

Immunodeficiency due to a late component of complements deficiency
0.76
age-related macular degeneration
0.58
macular degeneration
0.53
complement deficiency
0.46
immunodeficiency due to a late component of complement deficiency
0.37
wet macular degeneration
0.35
degeneration of macula and posterior pole
0.35
atrophic macular degeneration
0.35
neurodegenerative disease
0.34
placental abruption
0.30

Score is the Open Targets composite evidence score (0-1). Higher = stronger gene-disease association.

Protein function (UniProt)

Complement component C9

Pore-forming component of the membrane attack complex (MAC), a multiprotein complex activated by the complement cascade, which inserts into a target cell membrane and forms a pore, leading to target cell membrane rupture and cell lysis (PubMed:22832194, PubMed:26841837, PubMed:26841934, PubMed:27052168, PubMed:30552328, PubMed:6177822, PubMed:9212048, PubMed:9634479). The MAC is initiated by proteolytic cleavage of C5 into complement C5b in response to the classical, alternative, lectin and GZMK complement pathways (PubMed:39914456, PubMed:39814882, PubMed:9212048, PubMed:9634479). The complement pathways consist in a cascade of proteins that leads to phagocytosis and breakdown of pathogens and signaling that strengthens the adaptive immune system (PubMed:9212048, PubMed:9634479). Constitutes the pore-forming subunit of the MAC complex: during MAC assembly, C9 associates with the C5b8 intermediate complex, and polymerizes to complete the pore (PubMed:26841934, PubMed:30111885, PubMed:30552328, PubMed:34752492, PubMed:4055801, PubMed:6177822)

Curated MONDO disease pages that list C9 among their top associated genes.

age-related macular degenerationRare

Predicted protein structure

Clinical relevance (Genomics England PanelApp)

Disease associations (Open Targets)

Protein function (UniProt)

Diseases associated with C9