COL5A1 Gene

The COL5A1 gene (COL5A1 stands for "collagen type V alpha 1 chain") is a protein-coding gene located on chromosome 9q34.3.

The COL5A1 gene encodes an alpha chain for one of the low abundance fibrillar collagens. Alternative splicing of this gene results in multiple transcript variants.

Fibrillar collagen molecules are trimers that may consist of one or more types of alpha chains. Type V collagen is found in tissues containing type I collagen and appears to regulate the assembly of heterotypic fibers composed of both type I and type V collagen. Type V collagen forms only a small connective tissue component. It is distributed almost ubiquitously. Type V collagen binds to DNA, heparan sulfate, thrombospondin, heparin, and insulin.

The COL5A1- gene product is closely related to type XI coll agen, and it is possible that type V and XI collagen chains form a single collagen type with tissue-specific chain combinations. The encoded procollagen protein frequently occurs as the heterotrimer pro-alpha1(V)-pro-alpha1(V)-pro-alpha2(V).

Mutations in this gene are associated with Ehlers-Danlos syndrome, type I (classic type) and II. Furthermore, with multifocal fibromuscular dysplasia (I77.3), an arterial vascular disease (mainly of the internal carotid and renal arteries). It is characterized by proliferation of connective and muscular tissue in the vessel wall. This can lead to ischemic events in the downstream organs (or secondary hypertension in the case of the kidney) due to stenoses.

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