title: Clinical characteristics and genotype-phenotype correlation of hearing loss patients with SLC26A4 mutations.
abstract: CONCLUSIONS
  The present study confirmed the clinical characteristics of patients with SLC26A4 mutations: congenital, fluctuating, and progressive hearing loss usually associated with vertigo and/or goiter during long-term follow-up. This clarification should help to facilitate appropriate genetic counseling and proper medical management for patients with these mutations, but there was no particular genotype-phenotype correlation among them, suggesting that other factors may contribute to such variability.
  
  
  OBJECTIVE
  Due to the wide range of phenotypes caused by SLC26A4 mutations, there is controversy with regard to genotype-phenotype correlation. The present study was performed: (1) to determine phenotypic range in patients with biallelic SLC26A4 mutations, and (2) to evaluate whether possible genotype-phenotype correlation exists.
  
  
  METHODS
  Phenotypes in 39 hearing loss patients with SLC26A4 mutations were summarized and genotype-phenotype correlation was analyzed.
  
  
  RESULTS
  Hearing level varied in the individuals from mild to profound severity. Most of the patients had fluctuating and progressive hearing loss that may have been of prelingual onset. Twenty-four (70.6%) patients had episodes of vertigo, and 10 (27.8%) patients had goiter, which had appeared at age 12 or older. In contrast to such phenotypic variabilities, no apparent correlation was found between these phenotypes and their genotypes.
authors.affiliation: Department of Otorhinolaryngology, Shinshu University School of Medicine, Matsumoto, Japan.
authors.forename: Hiroaki
authors.initials: H
authors.lastname: Suzuki
authors.forename: Aki
authors.initials: A
authors.lastname: Oshima
authors.forename: Koji
authors.initials: K
authors.lastname: Tsukamoto
authors.forename: Satoko
authors.initials: S
authors.lastname: Abe
authors.forename: Kozo
authors.initials: K
authors.lastname: Kumakawa
authors.forename: Kyoko
authors.initials: K
authors.lastname: Nagai
authors.forename: Hitoshi
authors.initials: H
authors.lastname: Satoh
authors.forename: Yukihiko
authors.initials: Y
authors.lastname: Kanda
authors.forename: Satoshi
authors.initials: S
authors.lastname: Iwasaki
authors.forename: Shin-ichi
authors.initials: S
authors.lastname: Usami
mesh_terms: D000293:Adolescent; D000328:Adult; D000368:Aged; D044466:Asian People; D002648:Child; D002675:Child, Preschool; D005260:Female; D005838:Genotype; D006042:Goiter / Q000209:etiology; D006319:Hearing Loss, Sensorineural / Q000150:complications / Q000235:genetics* / Q000473:pathology; D006801:Humans; D007223:Infant; D007564:Japan; D008297:Male; D026901:Membrane Transport Proteins / Q000235:genetics*; D008875:Middle Aged; D009154:Mutation; D010641:Phenotype; D012189:Retrospective Studies; D000076988:Sulfate Transporters; D014717:Vertigo / Q000209:etiology; D014723:Vestibular Aqueduct / Q000473:pathology*
chemical_list: D026901:Membrane Transport Proteins; C085609:SLC26A4 protein, human; D000076988:Sulfate Transporters