Genetics Northern California

Treacher Collins Syndrome

Treacher Collins syndrome (TCS) is a congenital condition that involves the skull and face. TCS was first described by Toynbee and Thompson in 1846. Nearly 100 years later Berry and Treacher Collins described the essential components of the syndrome. Facial differences are bilateral (both sides) and usually symmetrical (equal). The face is narrow with underdeveloped eye socket rims, cheekbones, and jawbones which gives the nose the appearance of being large when it is actually normal in size.

Underdevelopment of the surrounding nasal bones and muscles as well as the pharynx can contribute to airway issues. The chin is receding. The eyelids are downward slanting with notching of the lower eyelids. Eyelashes are absent. The ear pinnae is malformed or misplaced, the external ear canal can be altered or absent. Bilateral conductive hearing loss is present. External ear tags as well as a patch of hair can extend onto the cheeks. A clefting of the palate and heart conditions can also be present. Intelligence is expected to be normal.

The cause of Treacher Collins has been traced to a specific gene called "Treacle". Although the mechanisms of gene action are not completely understood, we know that only about 40% of cases are inherited in an autosomal dominant fashion. The other 60% of cases are sporadic, or random, and are the result of a mutation in the child's DNA sequence.

The diagnosis of Treacher Collins syndrome is made based on the clinical findings described in the definition above.

Infants and children need to be evaluated and managed by a Craniofacial Team to identify immediate and long-term treatment plans. There are several interventions available to help reduce the physical differences found in Treacher Collins syndrome. Plastic and maxillofacial surgery intervention may help correct the underdevelopment of the cheekbones and jaw and small chin. When breathing difficulties are severe, due to jaw abnormalities and small nasal passages, mandibular distraction may be a consideration or a tracheostomy may need to be performed. With mild to moderate breathing issues supplemental oxygen and upright positioning may be sufficient intervention until the additional jaw growth occurs. The hearing loss is treated with bilateral bone conduction hearing aids as soon as possible in infancy. Infants and young children need to be placed in early intervention programs with hearing and speech specialists to facilitate speech and language development to help prevent delays and maximize the child's learning potential. Depending on the severity of ear and eye differences reconstructive surgery may be a consideration. If the young child has a cleft palate, surgery may be done around 1-2 years of age. During this surgery, ear tubes are commonly placed if the young child has had ear infections. . A speech evaluation will be done by a craniofacial speech pathologist a few months following surgery of the palate. Speech therapy may be instituted through early intervention programs or the school district. Because the child with a cleft palate is at risk for increased ear infections, hearing tests need to be performed regularly. Dental problems, due to the smallness of the mouth, are frequent and may require orthodontics and surgery. The Craniofacial Team will discuss options.

Other Information
As with so many of the craniofacial conditions, Treacher Collins syndrome varies considerably in its severity of presentation. Some children will have very obvious and severe characteristics and symptoms while others will only have a mild presentation and few difficulties.


Genetics Home Reference: Treacher Collins syndrome General information about Treacher Collins syndrome provided as a service of the National Library of Medicine. Also includes links to many related websites.

The National Craniofacial Association: Treacher Collins syndrome General information about Treacher Collins syndrome and links to related resources.