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Reviewed February 2008
What is the official name of the COL9A3 gene?
The official name of this gene is “collagen type IX alpha 3.”
COL9A3 is the gene's official symbol. The COL9A3 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 COL9A3 gene?
The COL9A3 gene provides instructions for making part of a large molecule called type IX collagen. Collagens are a family of proteins that strengthen and support connective tissues, such as skin, bone, cartilage, tendons, and ligaments. In particular, type IX collagen is an important component of cartilage.
Type IX collagen is made up of three proteins that are produced from three distinct genes: one α1(IX) chain, which is produced from the COL9A1 gene, one α2(IX) chain, which is produced from the COL9A2 gene, and one α3(IX) chain, which is produced from the COL9A3 gene. Type IX collagen is more flexible than other types of collagen molecules and is closely associated with type II collagen. Researchers believe that the flexible nature of type IX collagen allows it to act as a bridge that connects type II collagen with other cartilage components. Studies have shown that type IX collagen also interacts with the proteins produced from the MATN3 and COMP genes.
Does the COL9A3 gene share characteristics with other genes?
The COL9A3 gene belongs to a family of genes called COL (collagens). It also belongs to a family of genes called collagen proteoglycans (collagen proteoglycans). It also belongs to a family of genes called proteoglycans (proteoglycans).
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 COL9A3 gene related to health conditions?
Where is the COL9A3 gene located?
Cytogenetic Location: 20q13.3
Molecular Location on chromosome 20: base pairs 62,817,062 to 62,841,159
(Homo sapiens Annotation Release 107, GRCh38.p2) (
The COL9A3 gene is located on the long (q) arm of chromosome 20 at position 13.3.
More precisely, the COL9A3 gene is located from base pair 62,817,062 to base pair 62,841,159 on chromosome 20.
See How do geneticists indicate the location of a gene? in the Handbook.
Where can I find additional information about COL9A3?
You and your healthcare professional may find the following resources about COL9A3 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 COL9A3 gene or gene products?
See How are genetic conditions and genes named? in the Handbook.
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 COL9A3?
You may find definitions for these and many other terms in the Genetics Home Reference Glossary.
See also Understanding Medical Terminology.
References (6 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.