What Is Treacher Collins Syndrome (TCS)?
Treacher Collins syndrome (TCS) is a rare genetic craniofacial condition that occurs in approximately 1 in 25,000 births. It results from a bilateral combination of clefts through the malar and lateral orbital bones—known as Tessier clefts 6, 7 and 8—leading to a flattened cheek prominence, downward-slanting lower eyelids, and underdeveloped jaws and ears.
TCS is usually diagnosed based on physical examination and the distinctive facial features associated with the condition. Genetic testing can confirm the diagnosis by identifying mutations in the TCOF1, POLR1C, or POLR1D genes. If there is a known family history, prenatal diagnosis may also be possible.
Children with Treacher Collins syndrome may experience airway and breathing difficulties, hearing loss, dental alignment (occlusion) problems, and eyelid abnormalities. Despite these challenges, most children have normal intelligence and benefit greatly from coordinated care provided by an experienced craniofacial team.
What Is Nager Syndrome?
Nager syndrome shares many facial features with Treacher Collins syndrome but also involves differences in the arms and hands. It is most often caused by mutations in the SF3B4 gene, which plays a role in the development of facial and limb structures. The condition is typically inherited in an autosomal dominant manner, though many cases result from new mutations with no family history.
Like Treacher Collins syndrome, Nager syndrome can affect the facial bones, jaw, eyelids, and ears—but may also involve the thumbs, fingers, and elbows. Breathing and feeding challenges are common in infancy, though cognitive development is typically normal.
Common Characteristics
- Underdeveloped (hypoplastic) cheekbones
- Small or retrusive lower jaw and chin
- Downward slanting of the eyes
- Defects of the lower eyelids and eyelashes
- Malformed or absent ears
- Small or absent thumb (in Nager syndrome)
- Abnormal or fused fingers (syndactyly)
- Limited motion of the elbows
- Airway or breathing difficulties
- Feeding challenges in infancy
Diagnosis and Treatment
Children with Treacher Collins or Nager syndrome should be evaluated by a multidisciplinary craniofacial team including geneticists, surgeons, dentists, speech and hearing specialists, and psychosocial therapists. When breathing difficulties are present, airway management is the top priority.
Ongoing treatment plans may include correction of orbital and jaw differences, reconstruction of eyelids and ears, hearing and speech therapies, and orthodontic care. Because these syndromes may be associated with other conditions—such as spinal, heart, or urinary system differences—comprehensive genetic evaluation is recommended.
Our Expertise at Rady Children’s
The Craniofacial Services team at Rady Children’s Hospital–San Diego brings together highly experienced specialists in pediatric craniofacial surgery, plastic surgery, and genetic medicine. Our pediatric craniofacial plastic surgeons have extensive experience performing reconstructive procedures for Treacher Collins and Nager syndromes—addressing differences in the jaw, eyelids, facial bones, and other facial structures.
Our team also provides advanced surgical care for related craniofacial syndromes, including conditions that affect the eye sockets, jaw, and palate, such as cleft lip and cleft palate. Through our specialized craniofacial program, we offer coordinated care that improves both function and appearance—helping each child breathe, eat, hear, and thrive with confidence.