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Reviewed December 2013

What is the official name of the COL4A5 gene?

The official name of this gene is “collagen type IV alpha 5.”

COL4A5 is the gene's official symbol. The COL4A5 gene is also known by other names, listed below.

Read more about gene names and symbols on the About page.

What is the normal function of the COL4A5 gene?

The COL4A5 gene provides instructions for making one component of type IV collagen, which is a flexible protein. Specifically, this gene makes the alpha5(IV) chain of type IV collagen. This chain combines with two other types of alpha (IV) chains (the alpha3 and alpha4 chains) to make a complete type IV collagen molecule. Type IV collagen molecules attach to each other to form complex protein networks. These networks make up a large portion of basement membranes, which are thin sheet-like structures that separate and support cells in many tissues. Type IV collagen alpha3-4-5 networks play an especially important role in the basement membranes of the kidney, inner ear, and eye.

Does the COL4A5 gene share characteristics with other genes?

The COL4A5 gene belongs to a family of genes called COL (collagens).

A gene family is a group of genes that share important characteristics. Classifying individual genes into families helps researchers describe how genes are related to each other. For more information, see What are gene families? in the Handbook.

How are changes in the COL4A5 gene related to health conditions?

Alport syndrome - caused by mutations in the COL4A5 gene

More than 400 mutations in the COL4A5 gene have been found to cause Alport syndrome. Most of these mutations change single protein building blocks (amino acids) in a region where the alpha5(IV) collagen chain combines with other type IV collagen chains. Other mutations in the COL4A5 gene severely decrease or prevent the production of alpha5(IV) chains. As a result, there is a serious deficiency of the type IV collagen alpha3-4-5 network in the basement membranes of the kidney, inner ear, and eye. In the kidney, other types of collagen accumulate in the basement membranes, eventually leading to scarring of the kidneys and kidney failure. Mutations in this gene can also lead to abnormal function in the inner ear, resulting in hearing loss.

Where is the COL4A5 gene located?

Cytogenetic Location: Xq22

Molecular Location on the X chromosome: base pairs 108,439,736 to 108,697,545

(Homo sapiens Annotation Release 107, GRCh38.p2) (NCBIThis link leads to a site outside Genetics Home Reference.)

The COL4A5 gene is located on the long (q) arm of the X chromosome at position 22.

The COL4A5 gene is located on the long (q) arm of the X chromosome at position 22.

More precisely, the COL4A5 gene is located from base pair 108,439,736 to base pair 108,697,545 on the X chromosome.

See How do geneticists indicate the location of a gene? in the Handbook.

Where can I find additional information about COL4A5?

You and your healthcare professional may find the following resources about COL4A5 helpful.

You may also be interested in these resources, which are designed for genetics professionals and researchers.

What other names do people use for the COL4A5 gene or gene products?

  • ASLN
  • ATS
  • CA54
  • collagen IV, alpha-5 polypeptide
  • collagen of basement membrane, alpha-5 chain
  • collagen, type IV, alpha 5
  • collagen, type IV, alpha 5 (Alport syndrome)

Where can I find general information about genes?

The Handbook provides basic information about genetics in clear language.

These links provide additional genetics resources that may be useful.

What glossary definitions help with understanding COL4A5?

acids ; basal lamina ; basement membrane ; basement membranes ; benign ; collagen ; deficiency ; familial ; gene ; hematuria ; kidney ; molecule ; protein ; syndrome

You may find definitions for these and many other terms in the Genetics Home Reference Glossary.

See also Understanding Medical Terminology.

References (10 links)


The resources on this site should not be used as a substitute for professional medical care or advice. Users seeking information about a personal genetic disease, syndrome, or condition should consult with a qualified healthcare professional. See How can I find a genetics professional in my area? in the Handbook.

Reviewed: December 2013
Published: February 8, 2016