title: Inherited nonsyndromic hearing loss. An audiovestibular study in a large family with autosomal dominant progressive hearing loss related to DFNA2.
abstract: OBJECTIVE
  To study nonsyndromic progressive sensorineural hearing loss (SNHL) with significant linkage to the DFNA2 locus on chromosome 1p in a Dutch kindred.
  
  
  METHODS
  A 6-generation family with 194 family members was studied. Of the presumably affected persons, 43 were examined in detail to obtain audiograms and 37 underwent vestibulo-ocular examination.
  
  
  RESULTS
  Regression analysis showed significant and equal linear progression in SNHL with age (by about 1 dB per year) at all frequencies. Offset values were close to zero at the low frequencies (0.25, 0.5, and 1 kHz) but increased systematically with the frequency. It is likely that they represent congenital high-frequency SNHL: about 15 dB at 2 kHz, 30 dB at 4 kHz, and 50 dB at 8 kHz. Bilateral caloric weakness was not observed. A significant finding was that 25% to 35% (depending on the exclusion criteria) of the patients showed an increased vestibulo-ocular reflex (hyperreactivity) as measured by rotatory responses. Forty-one patients showed significant linkage to the 1p locus.
  
  
  CONCLUSIONS
  Including the present family, 4 families have been reported to show linkage to chromosome 1p. Statistical analysis of the audiological data shows a progression of 1 dB per octave per year in this type of progressive SNHL.
authors.affiliation: Department of Otorhinolaryngology, University Hospital Nijmegen, the Netherlands.
authors.forename: H
authors.initials: H
authors.lastname: Marres
authors.forename: M
authors.initials: M
authors.lastname: van Ewijk
authors.forename: P
authors.initials: P
authors.lastname: Huygen
authors.forename: H
authors.initials: H
authors.lastname: Kunst
authors.forename: G
authors.initials: G
authors.lastname: van Camp
authors.forename: P
authors.initials: P
authors.lastname: Coucke
authors.forename: P
authors.initials: P
authors.lastname: Willems
authors.forename: C
authors.initials: C
authors.lastname: Cremers
mesh_terms: D000328:Adult; D000368:Aged; D001301:Audiometry, Pure-Tone; D002878:Chromosomes, Human, Pair 1 / Q000235:genetics*; D005260:Female; D005799:Genes, Dominant; D008040:Genetic Linkage; D006319:Hearing Loss, Sensorineural / Q000175:diagnosis / Q000235:genetics*; D006801:Humans; D008297:Male; D008875:Middle Aged; D009426:Netherlands; D010375:Pedigree; D012027:Reflex, Vestibulo-Ocular / Q000502:physiology; D014724:Vestibular Function Tests