Treacher Collins Syndrome Associated with Disproportionate Nervous System, Cardiovascular, Otologic Complications Among 1,114 Patients.

We found a significantly elevated risk in TCS patients within all three systems. We postulate that the nervous system effects may be the result of one of the TCS-linked genes, for which a mutation has also been associated with progressive ataxia, cerebellar atrophy, hypomyelination, and seizures. As the previously-identified causal genes influence neural crest cells that form the head and face, these cells may also populate cardiac structures, resulting in cardiovascular abnormalities. Finally, the characteristic craniofacial abnormalities identified in TCS impair hearing and are associated with increased risk of otitis media. Our findings may help researchers to hypothesize the function of the genes underlying TCS, as well as to inform the care of affected individuals.