title: GJB2 deafness gene shows a specific spectrum of mutations in Japan, including a frequent founder mutation.
abstract: Mutations in the GJB2 gene (connexin 26) are the major cause of autosomal recessive non-syndromic hearing impairment in many populations. In contrast to the volume of information regarding the involvement of GJB2 mutations in hearing impairment in populations of European ancestry, less is known regarding other ethnic groups. In this study, we analyzed the GJB2 gene for mutations in 1227 hearing-impaired Japanese individuals. This revealed a unique spectrum of GJB2 mutations, different from that found in the Caucasian population. The most frequent mutation in Japanese, 235delC, has never been reported in Caucasians. To investigate a possible founder effect for the 235delC mutation, we analyzed single nucleotide polymorphisms in the vicinity of the GJB2 gene. Results were consistent with inheritance of the 235delC mutation from a common ancestor. The results of this study have important implications for genetic diagnostic testing for deafness in the Japanese population.
authors.affiliation: Department of Otorhinolaryngology, Shinshu University School of Medicine, 3-1-1 Asahi, 390-8621 Matsumoto, Japan.
authors.forename: Akihiro
authors.initials: A
authors.lastname: Ohtsuka
authors.forename: Isamu
authors.initials: I
authors.lastname: Yuge
authors.forename: Shinobu
authors.initials: S
authors.lastname: Kimura
authors.forename: Atsushi
authors.initials: A
authors.lastname: Namba
authors.forename: Satoko
authors.initials: S
authors.lastname: Abe
authors.forename: Lut
authors.initials: L
authors.lastname: Van Laer
authors.forename: Guy
authors.initials: G
authors.lastname: Van Camp
authors.forename: Shin-ichi
authors.initials: S
authors.lastname: Usami
mesh_terms: D000595:Amino Acid Sequence; D044466:Asian People / Q000235:genetics*; D016022:Case-Control Studies; D000072259:Connexin 26; D017630:Connexins / Q000235:genetics*; D003638:Deafness / Q000235:genetics; D018703:Founder Effect; D006319:Hearing Loss, Sensorineural / Q000235:genetics*; D006579:Heterozygote; D006720:Homozygote; D006801:Humans; D007564:Japan; D008969:Molecular Sequence Data; D009154:Mutation; D020641:Polymorphism, Single Nucleotide / Q000235:genetics*
chemical_list: D017630:Connexins; C000607042:GJB2 protein, human; D000072259:Connexin 26