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Reviewed June 2012

What is the official name of the TCOF1 gene?

The official name of this gene is “Treacher Collins-Franceschetti syndrome 1.”

TCOF1 is the gene's official symbol. The TCOF1 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 TCOF1 gene?

The TCOF1 gene provides instructions for making a protein called treacle. This protein is active during early embryonic development in structures that become bones and other tissues of the face, and it appears to play a critical role in the formation of these structures.

Studies suggest that treacle is involved in the production of a molecule called ribosomal RNA (rRNA), a chemical cousin of DNA. Ribosomal RNA helps assemble protein building blocks (amino acids) into functioning proteins, which is essential for the normal functioning and survival of cells. Treacle is active in the nucleolus, which is a small region inside the nucleus where rRNA is produced.

How are changes in the TCOF1 gene related to health conditions?

Treacher Collins syndrome - caused by mutations in the TCOF1 gene

About 200 mutations in the TCOF1 gene have been identified in people with Treacher Collins syndrome, a condition that affects the development of bones and other tissues of the face. Most of these mutations insert or delete a small number of DNA building blocks (base pairs) in the TCOF1 gene, which leads to a reduction in the amount of functional treacle in cells. As a result, the production of rRNA is reduced, which likely triggers the self-destruction (apoptosis) of certain cells involved in the early development of facial bones and tissues. Researchers believe that this abnormal cell death may lead to the specific problems with facial development found in Treacher Collins syndrome. However, it is unclear why the effects of a reduction in rRNA are limited to facial development.

Where is the TCOF1 gene located?

Cytogenetic Location: 5q32

Molecular Location on chromosome 5: base pairs 150,357,639 to 150,400,308

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

The TCOF1 gene is located on the long (q) arm of chromosome 5 at position 32.

The TCOF1 gene is located on the long (q) arm of chromosome 5 at position 32.

More precisely, the TCOF1 gene is located from base pair 150,357,639 to base pair 150,400,308 on chromosome 5.

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

Where can I find additional information about TCOF1?

You and your healthcare professional may find the following resources about TCOF1 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 TCOF1 gene or gene products?

  • TCS
  • Treacher Collins syndrome protein
  • treacle

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 TCOF1?

acids ; apoptosis ; cell ; DNA ; embryonic ; gene ; molecule ; nucleolus ; nucleus ; protein ; ribosomal RNA ; RNA ; syndrome

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

See also Understanding Medical Terminology.

References (11 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: June 2012
Published: February 8, 2016