Mandibulofacial dysostosis

Alternative names 
Treacher-Collins syndrome

Treacher-Collins syndrome is a hereditary condition that causes facial defects.

Causes, incidence, and risk factors

Treacher-Collins syndrome is inherited as an autosomal dominant trait. More than half of all cases are thought to be new mutations because there is no family history of the disease.

A defective gene, called treacle, is the cause of this disease. This condition has variable expression, which means there may be a great variation in severity from generation to generation.


  • Abnormal external ears to almost complete absence of an ear  
  • Hearing loss  
  • Very small jaw (micrognathia)  
  • Extra large mouth  
  • Defect in the lower eyelid (coloboma)  
  • Scalp hair extends onto cheeks  
  • Cleft palate

Signs and tests
The child usually will show normal intelligence. Examination of the infant can show various abnormalities, including:

  • Abnormal eye shape (palpebral fissure, antimongoloid slant)  
  • Flat cheekbones  
  • Facial clefts  
  • Small jaw  
  • Low-set ears  
  • Malformed ears  
  • Abnormal ear canal  
  • Conductive hearing loss  
  • Defects in the eye (coloboma that extends into the lower lid)  
  • Decreased eyelashes on the lower eyelid

Treatment consists of testing for and treating any hearing loss so a child can perform up to normal level in school. Plastic surgery can address the receding chin and other defects.

Support Groups

Treacher Collins Foundation

Expectations (prognosis)
Children with Treacher-Collins should grow to become normally functioning adults of normal intelligence. Careful attention to any hearing problems helps ensure better performance in school.


  • Feeding difficulty  
  • Speaking difficulty  
  • Communication problems  
  • Vision problems  
  • Cosmetic appearance can cause other people to think the problem is worse than it is

Calling your health care provider
This condition is usually apparent at birth. Call your health care provider if you have a child with Treacher-Collins syndrome and the hearing appears to be worse, or if other problems arise. A good plastic surgeon is very important as there is sometimes a need for a series of operations over years to correct birth defects.

Genetic counseling is appropriate for prospective parents with a family history of Treacher-Collins syndrome.

Johns Hopkins patient information

Last revised: December 2, 2012
by Arthur A. Poghosian, M.D.

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