Treacher Collins syndrome is a rare medical condition caused by a genetic mutation. It affects the development of bones and other tissues of the face and results in abnormalities in the head, face, and ears.

Other names for this syndrome are mandibulofacial dysostosis, Treacher Collins-Franceschetti syndrome, Franceschetti-Zwahlen-Klein syndrome, and zygoauromandibular dysplasia.

Treacher Collins syndrome (TCS) affects approximately 1 in 50,000 live births.

In this article, we examine the symptoms, causes, and treatments available for TCS. We also take a look at living with TCS and what the outlook is for people with the condition.

Signs and symptoms

Treacher Collins syndrome affects the facial bones and tissue, causing symptoms such as an underdeveloped jaw and chin.

The signs and symptoms of TCS vary and range from almost unnoticeable to severe.

While some individuals may experience very mild symptoms, others have extremely severe symptoms that may have serious consequences, such as life-threatening airway problems.

Signs and symptoms of TCS include some parts of the body developing in an abnormally or incompletely: These body areas include:

  • eyes, including lazy eye, an inability to focus, and vision loss
  • lower eyelids, which may include notching and sparse or absent eyelashes
  • cheekbones and jaw
  • chin
  • ears, which may include absent, small, malformed, or rotated ears
  • hair displacement, in which hair grows in front of the ears and to the lateral cheekbones
  • an opening in the roof of the mouth called a cleft palate, with or without a cleft lip
  • airways
  • skull
  • nose
  • teeth

Hearing loss may occur due to abnormal development of the facial bones and incomplete or abnormal development of the ears.

TCS may also cause a delay in motor and speech development.