a.k.a. Treacher-Collins-Franceschetti

Main Features

Bilateral characteristic facial features: malar and mandibular hypoplasia, microstomia, coloboma of outer third of lower lid, external and middle ear anomalies Eye Findings

External: lateral canthus displaced downward (antimongolid slant) Lids: Coloboma of outer 1/3 of lower lid, lack of cilia of medial lower lid, absence of lower puncta, absence of meibomian glands Iris: coloboma Motility: Esotropia Etiology

Autosomal Dominant Mutation in the 'treacle' gene (TCOF1; 606847) Gene map locus 5q32-q33.1 35 total reported mutations which represented a detection rate of 60% Incomplete penetrance and variable expressivity Other Findings

Zygomatic bone may be absent Conductive hearing loss Cleft palate Normal intelligence

References

Dixon, M. J. : Treacher Collins syndrome. Hum. Molec. Genet. 1996: 1391-1396, 1996 OMIM: #154500 Photo: American Academy of Ophthalmology