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Reviewed April 2014

What is the official name of the ALX1 gene?

The official name of this gene is “ALX homeobox 1.”

ALX1 is the gene's official symbol. The ALX1 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 ALX1 gene?

The ALX1 gene provides instructions for making a protein that is a member of the homeobox protein family. Homeobox proteins direct the formation of body structures during early embryonic development. The ALX1 protein is necessary for normal development of the head and face, particularly the formation of the eyes, nose, and mouth, which begins around the fourth week of development. The ALX1 protein is a transcription factor, which means that it attaches (binds) to DNA and controls the activity of certain genes. Specifically, the protein controls the activity of genes that regulate cell growth and division (proliferation) and movement (migration), ensuring that cells grow and stop growing at specific times and that they are positioned correctly during development.

Does the ALX1 gene share characteristics with other genes?

The ALX1 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 ALX1 gene related to health conditions?

frontonasal dysplasia - caused by mutations in the ALX1 gene

At least three mutations in the ALX1 gene have been found to cause frontonasal dysplasia. ALX1 gene mutations cause a form of the disorder called frontonasal dysplasia type 3, which is characterized by severe malformations of the structures at the center of the face. ALX1 gene mutations that cause this condition alter the protein's structure and impair its ability to bind to DNA and regulate gene function. As a result, the proliferation and migration of cells during development is not controlled, which can lead to small or missing eyes, openings (clefts) in the nose or mouth, and other severe facial malformations characteristic of frontonasal dysplasia type 3.

Where is the ALX1 gene located?

Cytogenetic Location: 12q21.31

Molecular Location on chromosome 12: base pairs 85,279,795 to 85,301,784

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

The ALX1 gene is located on the long (q) arm of chromosome 12 at position 21.31.

The ALX1 gene is located on the long (q) arm of chromosome 12 at position 21.31.

More precisely, the ALX1 gene is located from base pair 85,279,795 to base pair 85,301,784 on chromosome 12.

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

Where can I find additional information about ALX1?

You and your healthcare professional may find the following resources about ALX1 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 ALX1 gene or gene products?

  • ALX homeobox protein 1
  • CART1
  • CART-1
  • cartilage paired-class homeoprotein 1
  • epididymis luminal protein 23
  • FND3
  • HEL23

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 ALX1?

cartilage ; cell ; class ; DNA ; dysplasia ; embryonic ; epididymis ; gene ; homeobox ; proliferation ; protein ; 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 (5 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: April 2014
Published: February 8, 2016