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Reviewed August 2012
What is the official name of the PHOX2B gene?
The official name of this gene is “paired like homeobox 2b.”
PHOX2B is the gene's official symbol. The PHOX2B 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 PHOX2B gene?
The PHOX2B gene provides instructions for making a protein that acts early in development to help promote the formation of nerve cells (neurons) and regulate the process by which the neurons mature to carry out specific functions (differentiation). The protein is active in the neural crest, which is a group of cells in the early embryo that give rise to many tissues and organs. Neural crest cells migrate to form parts of the autonomic nervous system, which controls body functions such as breathing, blood pressure, heart rate, and digestion. Neural crest cells also give rise to many tissues in the face and skull, and other tissue and cell types.
The protein produced from the PHOX2B gene contains two areas where a protein building block (amino acid) called alanine is repeated multiple times. These stretches of alanines are known as polyalanine tracts or poly(A) tracts.
Does the PHOX2B gene share characteristics with other genes?
The PHOX2B gene belongs to a family of genes called homeobox (homeoboxes).
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 PHOX2B gene related to health conditions?
Where is the PHOX2B gene located?
Cytogenetic Location: 4p12
Molecular Location on chromosome 4: base pairs 41,744,082 to 41,748,970
(Homo sapiens Annotation Release 107, GRCh38.p2) (
The PHOX2B gene is located on the short (p) arm of chromosome 4 at position 12.
More precisely, the PHOX2B gene is located from base pair 41,744,082 to base pair 41,748,970 on chromosome 4.
See How do geneticists indicate the location of a gene? in the Handbook.
Where can I find additional information about PHOX2B?
You and your healthcare professional may find the following resources about PHOX2B 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 PHOX2B 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 PHOX2B?
acids ; alanine ; amino acid ; autonomic nervous system ; cancer ; cell ; cell proliferation ; colon ; congenital ; constipation ; deletion ; differentiation ; digestion ; DNA ; embryo ; familial ; gene ; homeobox ; homeodomain ; hypoventilation ; inherited ; intestine ; mesoderm ; mutation ; nerve cell ; nervous system ; neural crest ; neuroblasts ; neuron ; proliferation ; protein ; sporadic ; syndrome ; tissue ; tumor
You may find definitions for these and many other terms in the Genetics Home Reference Glossary.
See also Understanding Medical Terminology.
References (14 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.