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Reviewed July 2008

What is the official name of the COL11A1 gene?

The official name of this gene is “collagen type XI alpha 1.”

COL11A1 is the gene's official symbol. The COL11A1 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 COL11A1 gene?

The COL11A1 gene provides instructions for making one component of type XI collagen, called the pro-alpha1(XI) chain. Type XI collagen adds structure and strength to the connective tissues that support the body's muscles, joints, organs, and skin. Type XI collagen is normally found in cartilage, a tough but flexible tissue that makes up much of the skeleton during early development. Most cartilage is later converted to bone, except for the cartilage that continues to cover and protect the ends of bones and is present in the nose and external ears. Type XI collagen is also part of the clear gel that fills the eyeball (the vitreous), the inner ear, and the center portion of the discs between the vertebrae in the spine (nucleus pulposus).

The pro-alpha1(XI) chain combines with two other collagen chains (pro-alpha2(XI) and pro-alpha1(II)) to form a procollagen molecule. These triple-stranded, ropelike procollagen molecules are then processed by enzymes in the cell. Once processed, procollagen molecules leave the cell and arrange themselves into long, thin fibrils that link to one another (cross-link) in the spaces around cells. The cross-linkages result in the formation of very strong mature type XI collagen fibers.

Type XI collagen also helps maintain the spacing and diameter of type II collagen fibrils. Type II collagen is an important component of the eye and mature cartilage tissue. The size and arrangement of type II collagen fibrils is essential for the normal structure of these tissues.

Does the COL11A1 gene share characteristics with other genes?

The COL11A1 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 COL11A1 gene related to health conditions?

Stickler syndrome - caused by mutations in the COL11A1 gene

Mutations in the COL11A1 gene have been identified in some people with Stickler syndrome. Some mutations change one of the protein building blocks (amino acids) used to make the pro-alpha1(XI) chain. Other mutations cause segments of DNA to be skipped when the protein is being made, resulting in an abnormally short pro-alpha1(XI) chain. These alterations of type XI collagen impair its function, which can lead hearing loss, a tearing of the lining of the eye (retinal detachment), and abnormalities of the bones and joints.

Mutations in the COL11A1 gene are also responsible for some cases of Marshall syndrome, a disorder that is very similar to Stickler syndrome. In most mutations that cause this syndrome, a segment of DNA is skipped when the protein is made, resulting in an abnormally small pro-alpha1(XI) chain. This shortened protein hinders the formation of mature type XI collagen, which results in the features of Marshall syndrome. Whether Marshall syndrome represents a variant form of Stickler syndrome or a separate disorder is controversial.

other disorders - increased risk from variations of the COL11A1 gene

In some people, variations in the COL11A1 gene may increase the risk of developing osteoarthritis, a degenerative disease of joint cartilage. As a result of these genetic changes, incorrect amino acids are used in making the pro-alpha1(XI) chain of type XI collagen. The altered pro-alpha1(XI) chain may weaken collagen fibers, which could play a role in the erosion of cartilage in the joints, a characteristic feature of osteoarthritis.

Where is the COL11A1 gene located?

Cytogenetic Location: 1p21

Molecular Location on chromosome 1: base pairs 102,876,467 to 103,108,576

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

The COL11A1 gene is located on the short (p) arm of chromosome 1 at position 21.

The COL11A1 gene is located on the short (p) arm of chromosome 1 at position 21.

More precisely, the COL11A1 gene is located from base pair 102,876,467 to base pair 103,108,576 on chromosome 1.

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

Where can I find additional information about COL11A1?

You and your healthcare professional may find the following resources about COL11A1 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 COL11A1 gene or gene products?

  • COLL6
  • collagen, type XI, alpha 1
  • collagen XI, alpha-1 polypeptide
  • STL2

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 COL11A1?

acids ; cartilage ; cell ; collagen ; cross-link ; degenerative ; diameter ; DNA ; gene ; joint ; molecule ; nucleus ; Pro ; protein ; syndrome ; tissue

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

See also Understanding Medical Terminology.

References (9 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: July 2008
Published: February 8, 2016