title: Sensorineural hearing loss in people with deletions of 18q: hearing in 18q-.
abstract: OBJECTIVE
  The objective of this study was to characterize hearing loss in individuals with deletions of distal chromsome18q and to identify the smallest region of overlap of their deletions, thereby identifying potential causative genes.
  
  
  METHODS
  The clinical data were collected via a retrospective case study. Molecular data were obtained via high-resolution chromosome microarray analysis.
  
  
  METHODS
  The study was conducted as a component of the ongoing research protocols at the Chromosome 18 Clinical Research Center at the University of Texas Health Science Center at San Antonio.
  
  
  METHODS
  Thirty-eight participants with a deletion of the distal portion of the long arm of chromosome 18 were recruited to this study.
  
  
  METHODS
  The participants underwent an otologic examination as well as a basic audiometry evaluation. Blood samples were obtained, and high-resolution chromosome microarray analysis was performed.
  
  
  METHODS
  Pure tone averages and speech discrimination scores were determined for each participant. The region of hemizygosity for each participant was determined to within 2 Kb each of their breakpoints.
  
  
  RESULTS
  Twenty-four participants (63%) had high-frequency hearing loss, similar to the pattern seen in presbycusis. Comparison of microarray results allowed identification of eight genes, including the candidate gene for dysmyelination (MBP).
  
  
  CONCLUSIONS
  Individuals with a deletion of a 2.8 Mb region of 18q23 have a high probability (83%) of high-frequency sensorineural hearing loss.
authors.affiliation: *Ear Medical Group; †Department of Pediatrics, Chromosome 18 Clinical Research Center, University of Texas Health Science Center at San Antonio; ‡The Chromosome 18 Registry & Research Society; and §Department of Epidemiology and Biostatistics, University of Texas Health Science Center at San Antonio, San Antonio, Texas, U.S.A.
authors.forename: Brian P
authors.initials: BP
authors.lastname: Perry
authors.forename: Courtney
authors.initials: C
authors.lastname: Sebold
authors.forename: Minire
authors.initials: M
authors.lastname: Hasi
authors.forename: Patricia
authors.initials: P
authors.lastname: Heard
authors.forename: Erika
authors.initials: E
authors.lastname: Carter
authors.forename: Annice
authors.initials: A
authors.lastname: Hill
authors.forename: Jonathon
authors.initials: J
authors.lastname: Gelfond
authors.forename: Daniel E
authors.initials: DE
authors.lastname: Hale
authors.forename: Jannine D
authors.initials: JD
authors.lastname: Cody
mesh_terms: D000293:Adolescent; D000328:Adult; D001299:Audiometry; D002648:Child; D002675:Child, Preschool; D002872:Chromosome Deletion; D025063:Chromosome Disorders / Q000150:complications* / Q000503:physiopathology; D002887:Chromosomes, Human, Pair 18; D005260:Female; D006309:Hearing / Q000502:physiology*; D006319:Hearing Loss, Sensorineural / Q000209:etiology* / Q000503:physiopathology; D006801:Humans; D007223:Infant; D008297:Male; D012189:Retrospective Studies; D055815:Young Adult