title: Vestibular functions of hereditary hearing loss patients with GJB2 mutations.
abstract: OBJECTIVE
  Mutations in the GJB2 gene have been of particular interest as it is the most common causative gene for congenital deafness in all populations. Detailed audiological features, including genotype-phenotype correlations, have been well documented. However, in spite of abundant gene as well as protein expression in the vestibular end organs, neither vestibular symptoms nor vestibular functions have yet been elucidated. In the present study, vestibular functions were evaluated in patients diagnosed with GJB2-related deafness.
  
  
  METHODS
  Vestibular functions were evaluated by caloric test and cervical vestibular evoked myogenic potential (cVEMP) testing in 24 patients with biallelic GJB2 mutations.
  
  
  CONCLUSIONS
  Twenty-one of 23 patients (91.3%) had normal caloric responses and significantly lower cVEMP amplitudes than the control subjects. In the patients who were able to undergo vestibular testing, the mostly normal reactions to caloric testing indicated that the lateral semicircular canal was intact. However, the majority of GJB2 patients showed low cVEMP reactions, indicating a saccular defect.
authors.affiliation: Department of Otorhinolaryngology, Shinshu University School of Medicine, Matsumoto City, Japan.
authors.forename: Keita
authors.initials: K
authors.lastname: Tsukada
authors.forename: Hisakuni
authors.initials: H
authors.lastname: Fukuoka
authors.forename: Shin-Ichi
authors.initials: S
authors.lastname: Usami
mesh_terms: D000293:Adolescent; D000328:Adult; D002648:Child; D002675:Child, Preschool; D000072259:Connexin 26; D017630:Connexins / Q000235:genetics*; D005260:Female; D034381:Hearing Loss / Q000235:genetics / Q000503:physiopathology*; D006801:Humans; D008297:Male; D012665:Semicircular Canals / Q000503:physiopathology*; D058585:Vestibular Evoked Myogenic Potentials / Q000502:physiology*; D014724:Vestibular Function Tests; D014722:Vestibule, Labyrinth / Q000503:physiopathology*; D055815:Young Adult
chemical_list: D017630:Connexins; C000607042:GJB2 protein, human; D000072259:Connexin 26