TCOF1

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 in the face. Although the precise function of this protein is unknown, researchers believe that it plays a critical role in the development of facial bones and related structures.

Studies suggest that treacle is involved in the production of a molecule called ribosomal RNA (rRNA) within cells. Treacle is active in the nucleolus, which is a small region inside the nucleus where rRNA is produced. As a major component of cell structures called ribosomes, rRNA is essential for the assembly of proteins.

Treacher Collins syndrome - caused by mutations in the TCOF1 gene

About 150 mutations in the TCOF gene have been identified in people with Treacher Collins syndrome. 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 treacle in cells. A loss of treacle may reduce the production of rRNA in cells that contribute to the development of facial bones and tissues, signaling those cells to self-destruct (undergo apoptosis). Researchers believe that this abnormal cell death may lead to the specific problems with facial development found in Treacher Collins syndrome.