A Novel Insertion in Exon 23 of the TCOF1 Gene in a Newborn Infant with Treacher Collins Syndrome

Treacher Collins syndrome (TCS) is the most common and well known mandibulofacial dysostosis with characteristic clinical features including downward slanting of palpebral fissures, coloboma of the lower eyelid, hypoplastic zygomatic arches, micrognathia, macrostomia, microtia, and other deformities of the ears. TCS is caused by mutations in at least 3 genes involved in pre-rRNA transcription: TCOF1, POLR1D and POLR1C. We experienced a 1-day-old female infant with characteristic clinical features of TCS. A novel, heterozygotic mutation within the TCOF1 gene (c.3874_3875insG, p.Ala1292Glyfs*30) was identified to cause a premature stop codon.