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Reviewed February 2006

What is the official name of the COL4A5 gene?

The official name of this gene is “collagen, type IV, alpha 5 (Alport syndrome).”

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

What is the normal function of the COL4A5 gene?

The COL4A5 gene carries the instructions for making one component of type IV collagen, which is a flexible protein that forms complex networks. 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 collagen molecule. Type IV collagen networks make up a large portion of basement membranes, which are thin sheet-like structures that separate and support cells in many tissues. This type IV collagen network plays an especially important role in the basement membranes of the kidney, inner ear, and eye.

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

Alport syndrome - caused by mutations in the COL4A5 gene

Mutations in the COL4A5 gene cause approximately 80 percent of Alport syndrome cases. Several hundred different mutations have been identified, the majority of which cause a change in the sequence of amino acids (the building blocks of proteins) in a region of the alpha5(IV) collagen chain that is critical for combining with other type IV collagen chains. Other mutations severely decrease or prevent the production of the alpha5(IV) chains. As a result, there is a serious deficiency of the type IV collagen 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 107,569,809 to 107,827,430

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 107,569,809 to base pair 107,827,430 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

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 ; amino acid ; benign ; cell ; collagen ; deficiency ; familial ; gene ; hematuria ; kidney ; molecule ; mutation ; polypeptides ; protein ; syndrome ; tissue

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

References (8 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: February 2006
Published: January 23, 2009