To report the phenotype-genotype correlation in a Belgian family that was ascertained to have a novel missense mutation in the NOG gene mapping to chromosome 17q22.
To describe the phenotype, a retrospective case study was performed based on the otologic, audiologic, ophthalmologic, and radiologic data of the mutation carriers of the NOG gene.
Tertiary referral center.
All members of a Belgian kindred who carried the novel missense mutation in the NOG gene (NOG, Trp205Cys [W205C]; 1426G>C).
Diagnostic otologic and ophthalmologic examination, audiometric analysis, and radiologic imaging.
All five mutation carriers had a typical facies. Bilateral proximal symphalangism and hyperopia were present in 80%. Five of 10 ears also had progressive early-onset conductive hearing loss caused by stapes ankylosis.
So far, 14 independent NOG mutations have been identified. The autosomal dominant disorder described in the present family was caused by a novel NOG missense mutation (NOG, Trp205Cys [W205C]; 1426G>C). The phenotype correlated well with the facioaudiosymphalangism syndrome. The mutation carriers demonstrated progressive multiple joint fusions, hyperopia, early-onset conductive deafness, and a typical facies.
*Department of Oto-Rhino-Laryngology and †Department of Medical Genetics, University of Antwerp, and ‡Department of Radiology and §Department of Pediatrics, St-Lucas Hospital, Brugge, Belgium
Address correspondence and reprint requests to: Frank Declau, M.D., Ph.D., Department of ENT, Head & Neck Surgery, University Hospital of Antwerp, Wilrijkstraat 10, 2650 Edegem, Belgium; E-mail: firstname.lastname@example.org