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COL4A4

COL4A4

Reviewed December 2013

What is the official name of the COL4A4 gene?

The official name of this gene is “collagen, type IV, alpha 4.”

COL4A4 is the gene's official symbol. The COL4A4 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 COL4A4 gene?

The COL4A4 gene provides instructions for making one component of type IV collagen, which is a flexible protein. Specifically, this gene makes the alpha4(IV) chain of type IV collagen. This chain combines with two other types of alpha (IV) chains (the alpha3 and alpha5 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.

How are changes in the COL4A4 gene related to health conditions?

Alport syndrome - caused by mutations in the COL4A4 gene

More than 20 mutations in the COL4A4 gene have been found to cause Alport syndrome. Most of these mutations change single protein building blocks (amino acids) in a region where the alpha4(IV) collagen chain combines with other type IV collagen chains. Other mutations in the COL4A4 gene severely decrease or prevent the production of alpha4(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.

other disorders - caused by mutations in the COL4A4 gene

Mutations in the COL4A4 gene have been found to cause thin basement membrane nephropathy. This condition typically causes people to have blood in their urine (hematuria) but no other signs or symptoms of kidney disease. In the past, this condition was often called benign familial hematuria. Thin basement membrane nephropathy rarely progresses to kidney failure.

Where is the COL4A4 gene located?

Cytogenetic Location: 2q35-q37

Molecular Location on chromosome 2: base pairs 226,968,915 to 227,164,558

The COL4A4 gene is located on the long (q) arm of chromosome 2 between positions 35 and 37.

The COL4A4 gene is located on the long (q) arm of chromosome 2 between positions 35 and 37.

More precisely, the COL4A4 gene is located from base pair 226,968,915 to base pair 227,164,558 on chromosome 2.

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

Where can I find additional information about COL4A4?

You and your healthcare professional may find the following resources about COL4A4 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 COL4A4 gene or gene products?

  • alpha 4 type IV collagen
  • CA44
  • CO4A4_HUMAN
  • Collagen IV, alpha-4 polypeptide
  • collagen of basement membrane, alpha-4 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 COL4A4?

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

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

See also Understanding Medical Terminology.

References (12 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: July 7, 2014