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SOX 9 Gene

Source:  http://ghr.nlm.nih.gov/gene/SOX9


What genes are related to isolated Pierre Robin sequence?

Changes in the DNA near the SOX9 gene are the most common genetic cause of isolated Pierre Robin sequence. It is likely that changes in other genes, some of which have not been identified, also cause isolated Pierre Robin sequence.


The SOX9 gene provides instructions for making a protein that plays a critical role in the formation of many different tissues and organs during embryonic development. The SOX9 protein regulates the activity of other genes, especially those that are important for development of the skeleton, including the mandible.


The genetic changes associated with isolated Pierre Robin sequence occur near the SOX9 gene. These abnormalities are thought to disrupt regions of DNA called enhancers that normally regulate the activity of the SOX9 gene, reducing SOX9 gene activity. As a result, the SOX9 protein cannot properly control the genes essential for normal development of the lower jaw, causing micrognathia, and consequently, glossoptosis and cleft palate.


What is the official name of the SOX9 gene?

The official name of this gene is “SRY (sex determining region Y)-box 9.”SOX9 is the gene’s official symbol. The SOX9 gene is also known by other names, listed below.


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)-box genes).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.


How are changes in the SOX9 gene related to health conditions?

campomelic dysplasia – caused by mutations in the SOX9 gene

More than 45 mutations involving the SOX9 gene have been found to cause campomelic dysplasia, a disorder that affects the development of the skeleton and reproductive system 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 around the SOX9 gene. These chromosome abnormalities disrupt regions of DNA called enhancers that normally regulate the activity of theSOX9 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 around 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, reducing SOX9 gene activity. As a result, the SOX9 protein cannot properly control the genes essential for normal development of the lower jaw, causing micrognathia. Underdevelopment of the lower jaw affects placement of the tongue and formation of the palate, leading to glossoptosis and cleft palate. Researchers suggest that the enhancers disrupted by the genetic changes that cause Pierre Robin sequence are specifically involved in controlling SOX9 gene activity during development of the lower jaw, leading to the small number of features of the condition.


Where is the SOX9 gene located?

Cytogenetic Location: 17q23Molecular Location on chromosome 17: base pairs 70,117,160 to 70,122,560

The SOX9 gene is located on the long (q) arm of chromosome 17 at position 23. More precisely, the SOX9 gene is located from base pair 70,117,160 to base pair 70,122,560 on chromosome 17.