Treacher Collins syndrome (also known as "Treacher Collins–Franceschetti syndrome" or TCS) is a rare genetic disorder characterized by craniofacial deformities.:577 Treacher Collins syndrome is found in 1 in 10,000 births. The typical physical features include downward slanting eyes, micrognathia (a small lower jaw), conductive hearing loss, underdeveloped zygoma, drooping part of the lateral lower eyelids, and malformed or absent ears. Most cases have normal intelligence, although hearing and visual impairmants may lead to an erroneous diagnosis of intellectual disability. 
One known cause of this syndrome is a mutation in the TCOF1 gene, at chromosome 5q32-q33.1. The protein coded by this gene is called treacle and has been hypothesized to assist in protein sorting during particular stages in embryonic development, particularly that of the structures of the head and face. The disorder is inherited in an autosomal-dominant pattern.
The signs of this disorder vary greatly, ranging from almost unnoticeable to severe. Most affected patients have underdeveloped facial bones, which result in a sunken appearance in the middle of the face, a prominent nose, and a very small jaw and chin (micrognathia). Some people with this condition are also born with a cleft palate. Malocclusion of teeth also is present. In severe cases, the micrognathia may displace the tongue of an affected neonate (new-born) sufficiently to cause obstruction of the oropharynx and potentially life-threatening respiratory problems, but it has been known that the epiglottis can be surgically removed to help in airway obstruction. The neonate will asphyxiate unless a proper airway is established. The condition is bilateral (occurring on both sides of the face) and the involvement is symmetrical. Congenital heart disease is an unusual feature.
People with Treacher Collins syndrome often have eyes that slant downward, sparse eyelashes, and a notch in the lower eyelids called a coloboma. The coloboma is at the junction of lateral 1/3 and middle 1/3 of lower lid which is associated with other congenital abnormalities apart from Treacher Collins syndrome. People with Treacher Collins syndrome may also need a feeding tube because some cases are so severe that they cannot swallow. This condition is also characterized by absent, small, or unusually formed ears (pinnae), called microtia. Defects in the middle ear (which contains three small bones that transmit sound) cause hearing loss in about half of cases. People with Treacher Collins syndrome usually have normal intelligence.
People with the syndrome can undergo operations on the face to improve appearance, get hearing aids, and can also undergo surgery on a cleft palate. Moderate defects of the lid notch (Coloboma) can be corrected by primary surgical closure. Large defects might need skin grafts and rotational flaps to correct the notch.
- ↑ Rapini, Ronald P.; Bolognia, Jean L.; Jorizzo, Joseph L. (2007). Dermatology: 2-Volume Set, 894, 1686, St. Louis: Mosby.
- ↑ James, William; Berger, Timothy; Elston, Dirk (2005). Andrews' Diseases of the Skin: Clinical Dermatology. (10th ed.). Saunders. ISBN 0721629210.
- ↑ Reber, A.S. & Reber, E.S (2001) Dictionary of Psychology. London:Penguin
- ↑ Who Named It synd/1416
- GeneReview/NCBI/NIH/UW entry on Treacher Collins Syndrome
- http://www.friendlyfaces.org/ is a resource for, and network of, individuals with facial differences, parents, families, friends, and health care professionals