Audiovestibular phenotype associated with a COL11A1 mutation in Marshall syndrome

Background: Marshall syndrome is a dominant disorder characterized by craniofacial and skeletal abnormalities, sensorineural hearing loss, myopia, and cataracts, and is associated with splicing mutations in COL11A1. Objective: To determine the auditory and vestibular phenotypes associated with a COL11A1 splicing. Design: Clinical otolaryngologic, audiologic, vestibular, and radiologic evaluations of the auditory and vestibular systems. Subjects: Three affected individuals from a family cosegregating Marshall syndrome and a COL11A1 splice site mutation. Results: The study subjects have progressive sensorineural hearing loss that is predominantly cochlear in origin and asymptomatic dysfunction of the central and peripheral vestibular systems. Computed tomography detected no malformations of temporal bone structures. Conclusions: The observed auditory and vestibular abnormalities are not caused by defective morphogenesis of the osseous labyrinth, but by more direct effects of the COL11A1 mutation on the membranous labyrinth and the central nervous system. The onset and degree of hearing loss associated with COL11A1 mutations are useful clinical features to differentiate Marshall syndrome from the phenotypically similar Stickler syndrome.