Autosomal dominant inherited hearing impairment caused by a missense mutation in COL11A2 (DFNA13)

Objective: To analyze the phenotype in a 5-generation DFNA13 family with a missense mutation in the COL11A2 gene that causes autosomal dominant, presu mably prelingual, nonsyndromic sensorineural hearing impairment. Design: Family study. Setting: University hospital department. Patients: Twenty mutation carriers from a large American kindred. Methods: Cross-sectional analysis using pure-tone threshold measurements at 0.25, 0.5, 1, 2, 4, and 8 kHz. The audiometric configuration was evaluated according to an existing consensus protocol. The significance of features relating to audiometric configuration was tested using 1-way analysis of va riance. Progression was evaluated with linear regression analyses of thresh old-on-age. Results: Most individuals showed midfrequency (U-shaped) characteristics. T he mean threshold in generations IV and V was 44 dB at 1, 2, and 4 kHz (mid frequencies); it was 29 dB at the other frequencies (0.25, 0.5, and 8 kHz). There was no significant progression beyond presbyacusis. Conclusion: The trait in this family can be characterized as autosomal domi nant, nonprogressive, presumably prelingual, midfrequency sensorineural hea ring impairment.