A novel missense mutation in a C2 domain ofOTOF results in autosomal recessive auditory neuropathy

Division of Pediatric Molecular Genetics, Ankara University School of Medicine, Ankara, Turkey.
American Journal of Medical Genetics Part A (Impact Factor: 2.05). 09/2005; 138(1):6-10. DOI: 10.1002/ajmg.a.30907
Source: PubMed

ABSTRACT Screening of 12 Turkish families with apparently autosomal recessive nonsyndromic sensorineural deafness without GJB2 and mtDNA m.1555A > G mutations for 11 previously mapped recessive deafness loci showed a family in which hearing loss cosegregated with the DFNB9 (OTOF) locus. Three affected children were later found to carry a novel homozygous c.3032T > C (p.Leu1011Pro) mutation in the OTOF gene. Both parents were heterozygous for the mutation. p.Leu1011Pro alters a conserved leucine residue in the C2D domain of otoferlin. Pure tone audiometry of the family showed severe to profound sensorineural hearing loss (with U-shape audiograms) in children, and normal hearing in the parents. Otoacoustic emissions and auditory brainstem response (ABR) suggested the presence of auditory neuropathy in affected individuals.

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