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Reviewed August 2013

What is the official name of the SOX9 gene?

The official name of this gene is “SRY-box 9.”

SOX9 is the gene's official symbol. The SOX9 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 SOX9 gene?

The SOX9 gene provides instructions for making a protein that plays a critical role during embryonic development. The SOX9 protein is especially important for the development of the skeleton and reproductive system. This protein attaches (binds) to specific regions of DNA and regulates the activity of other genes. On the basis of this action, the SOX9 protein is called a transcription factor.

Does the SOX9 gene share characteristics with other genes?

The SOX9 gene belongs to a family of genes called SOX (SRY (sex determining region Y)-boxes).

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 SOX9 gene related to health conditions?

campomelic dysplasia - caused by mutations in the SOX9 gene

More than 60 mutations involving the SOX9 gene have been found to cause campomelic dysplasia, a disorder that affects the development of the skeleton, reproductive system, and other parts of the body and is often life-threatening in the newborn period. Most cases of campomelic dysplasia are caused by mutations within the SOX9 gene. These mutations prevent the production of the SOX9 protein or result in a protein with impaired ability to function as a transcription factor. About 5 percent of cases are caused by chromosome abnormalities that occur near the SOX9 gene. These chromosome abnormalities disrupt regions of DNA called enhancers that normally regulate the activity of the SOX9 gene. All of these genetic changes prevent the SOX9 protein from properly controlling the genes essential for normal development of the skeleton, reproductive system, and other parts of the body. Abnormal development of these structures causes the signs and symptoms of campomelic dysplasia.

Individuals with milder forms of campomelic dysplasia are more likely to have chromosome abnormalities near the SOX9 gene than mutations within the gene.

isolated Pierre Robin sequence - caused by mutations in the SOX9 gene

Genetic changes that occur near the SOX9 gene cause some cases of isolated Pierre Robin sequence. Individuals with this condition have a small lower jaw (micrognathia), a tongue that is placed further back than normal (glossoptosis), and an opening in the roof of the mouth (a cleft palate). These cases of Pierre Robin sequence are described as isolated because they occur without other signs and symptoms.

The genetic changes associated with isolated Pierre Robin sequence are thought to disrupt enhancer regions that normally regulate the activity of the SOX9 gene during development of the lower jaw, which reduces SOX9 gene activity. As a result, the SOX9 protein cannot properly control the genes essential for normal jaw development, causing micrognathia. Underdevelopment of the lower jaw affects placement of the tongue and formation of the palate, leading to glossoptosis and cleft palate.

Genetics Home Reference provides information about Swyer syndrome, which is also associated with changes in the SOX9 gene.

Where is the SOX9 gene located?

Cytogenetic Location: 17q24.3

Molecular Location on chromosome 17: base pairs 72,121,020 to 72,126,420

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

The SOX9 gene is located on the long (q) arm of chromosome 17 at position 24.3.

The SOX9 gene is located on the long (q) arm of chromosome 17 at position 24.3.

More precisely, the SOX9 gene is located from base pair 72,121,020 to base pair 72,126,420 on chromosome 17.

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

Where can I find additional information about SOX9?

You and your healthcare professional may find the following resources about SOX9 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 SOX9 gene or gene products?

  • SRA1
  • SRY box 9
  • SRY (sex determining region Y)-box 9
  • SRY (sex-determining region Y)-box 9 protein
  • transcription factor SOX9

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 SOX9?

chromosome ; cleft palate ; DNA ; dysplasia ; embryonic ; enhancer ; gene ; lower jaw ; micrognathia ; palate ; protein ; syndrome ; transcription ; transcription factor

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

See also Understanding Medical Terminology.

References (13 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: August 2013
Published: February 8, 2016