title: Prevalence of GJB2-associated deafness and outcomes of cochlear implantation in Iran.
abstract: OBJECTIVE
  To investigate the prevalence of mutations in the coding exon of the GJB2 gene in Iranian children with cochlear implants, and to compare the outcomes of auditory perception and speech production in cochlear-implanted children with and without GJB2 mutation.
  
  
  METHODS
  One hundred and sixty-six prelingually deaf children who had undergone cochlear implantation at the Iranian Cochlear Implant Center, Tehran, were selected from a pool of 428 implanted children. The prevalence of GJB2 gene mutations was assessed using nested polymerase chain reaction and direct sequencing. To enable comparisons, we also identified 36 implanted children with non-GJB2 deafness. Patients' speech perception and speech production were assessed using the Categorization of Auditory Performance and Speech Intelligibility Rating scales.
  
  
  RESULTS
  Thirty-three of 166 probands (19.9 per cent) were found to have GJB2 deafness-causing allele variants and were diagnosed with DFNB1 deafness. Results also indicated a significant improvement in speech perception and production scores in both GJB2 and non-GJB2 patients over time.
  
  
  CONCLUSIONS
  Children with GJB2-related deafness benefit from cochlear implantation to the same extent as those with non-GJB2-related deafness.
authors.affiliation: Head and Neck Surgery Department and Research Center, Iran University of Medical Sciences, Tehran, Iran. daneshi@daneshi.net
authors.forename: A
authors.initials: A
authors.lastname: Daneshi
authors.forename: S
authors.initials: S
authors.lastname: Hassanzadeh
authors.forename: H
authors.initials: H
authors.lastname: Emamdjomeh
authors.forename: S H
authors.initials: SH
authors.lastname: Mohammadi
authors.forename: S
authors.initials: S
authors.lastname: Arzhangi
authors.forename: M
authors.initials: M
authors.lastname: Farhadi
authors.forename: H
authors.initials: H
authors.lastname: Najmabadi
mesh_terms: D000293:Adolescent; D000328:Adult; D016022:Case-Control Studies; D002648:Child; D002675:Child, Preschool; D002853:Chromatography, Liquid / Q000379:methods; D019929:Cochlear Implantation; D000072259:Connexin 26; D017630:Connexins / Q000235:genetics*; D003638:Deafness / Q000453:epidemiology / Q000235:genetics / Q000534:rehabilitation; D005787:Gene Frequency; D005838:Genotype; D006801:Humans; D007223:Infant; D007231:Infant, Newborn; D007492:Iran / Q000453:epidemiology; D009154:Mutation / Q000235:genetics; D016133:Polymerase Chain Reaction; D015995:Prevalence; D013063:Speech Discrimination Tests; D013065:Speech Intelligibility / Q000502:physiology*; D013067:Speech Perception / Q000502:physiology*; D013068:Speech Production Measurement; D016896:Treatment Outcome; D055815:Young Adult
chemical_list: D017630:Connexins; C000607042:GJB2 protein, human; D000072259:Connexin 26