title: GJB2 (Connexin 26) gene mutations among hearing-impaired persons in a Swedish cohort.
abstract: CONCLUSIONS
  The most common mutation in the Swedish population was Connexin 26 (C×26) 35delG, which indicates that the percentage of Swedish persons with C×26 mutations and polymorphisms in the GJB2 gene among non-syndromic hearing-impaired (HI) persons is comparable to the rest of Europe. The results strongly support a Swedish policy to offer all children with diagnosed hearing impairment genetic tests for the C×26 35delG mutation.
  
  
  OBJECTIVE
  The aim of the present study was to search for mutations in the GBJ2 gene among Swedish persons with non-syndromic hearing impairment to further clarify how common these mutations are in Sweden, one of the northernmost countries in Europe.
  
  
  METHODS
  Seventy-nine patients with non-syndromic hearing impairment participated in the study. For 87% of the participants, a pure tone audiogram showed a severe or profound hearing impairment. Dried blood spots on filter paper, taken at 3-5 days of age in the Swedish nationwide neonatal screening programme for congenital disorders and saved in a biobank, were used for the molecular genetic analyses.
  
  
  RESULTS
  The total number of subjects with one or two pathologic mutations or a mutation of unknown consequence found in the GJB2 gene was 28 of 79 (35%). Nineteen (19) persons (24%) were homozygotes for the 35delG mutation.
authors.affiliation: Department of Otorhinolaryngology, Central Hospital, Karlstad, Sweden. per-inge.carlsson@liv.se
authors.forename: Per-Inge
authors.initials: PI
authors.lastname: Carlsson
authors.forename: Eva
authors.initials: E
authors.lastname: Karltorp
authors.forename: Eva
authors.initials: E
authors.lastname: Carlsson-Hansén
authors.forename: Henrik
authors.initials: H
authors.lastname: Åhlman
authors.forename: Claes
authors.initials: C
authors.lastname: Möller
authors.forename: Ulrika
authors.initials: U
authors.lastname: Vondöbeln
mesh_terms: D000483:Alleles; D002648:Child; D002872:Chromosome Deletion; D015331:Cohort Studies; D000072259:Connexin 26; D017630:Connexins / Q000235:genetics*; D003430:Cross-Sectional Studies; D004252:DNA Mutational Analysis; D003638:Deafness / Q000453:epidemiology / Q000235:genetics*; D004519:Education, Special; D006580:Genetic Carrier Screening; D005828:Genetics, Population; D034381:Hearing Loss / Q000453:epidemiology / Q000235:genetics*; D006720:Homozygote; D006801:Humans; D016133:Polymerase Chain Reaction; D011110:Polymorphism, Genetic / Q000235:genetics; D017422:Sequence Analysis, DNA; D013548:Sweden
chemical_list: D017630:Connexins; C000607042:GJB2 protein, human; D000072259:Connexin 26