In Wonder, Auggie Pullman reveals that he was born with a condition called mandibulofacial dysostosis, which is more commonly known as Treacher Collins Syndrome. This condition is very rare, occurring in only 1 in 50,000 births. It gets its name from surgeon Edward Treacher Collins, who first described its traits in 1900.
Treacher Collins Syndrome affects the development of bones and other facial tissues. How prevalent the signs and symptoms of this disorder are can vary greatly. In some children the condition is almost unnoticeable, but in others, like Auggie, the symptoms are severe. Hallmarks of this syndrome are underdeveloped cheek bones, a small jaw and chin, a cleft palate, and eyes that slant downward.
But these abnormalities can have effects that go beyond appearance. Underdeveloped facial bones may restrict an infant's airway, resulting in respiratory problems. Some of the eye abnormalities can lead to vision loss, and unusual ear formation may result in hearing loss. Auggie experiences this last problem and eventually requires hearing aids in order to hear properly. A similar form of hearing impairment occurs in about 50% of affected individuals.
TCS cannot be cured, but certain treatments may address its symptoms. Plastic surgery can help to normalize facial structure, and other procedures can be undertaken to correct jaw problems, cleft palates, and other facial abnormalities. Surgery can also address hearing and vision problems. Some children born with TCS have problems speaking; if this is the case, the child may be sent to speech therapy from an early age.