Frequencies of GJB2 mutations in German control individuals and patients showing sporadic non-syndromic hearing impairment.
Mutations in the GJB2 gene encoding the gap-junction protein connexin 26 have been identified in many patients with childhood hearing impairment (HI). One single mutation, 35delG (30delG), accounts for up to 70% of all analyzed European patients with autosomal recessive inherited HI and 10% of patients with HI of unknown origin, respectively. We screened 188 control individuals and 342 German patients with non-syndromic sporadic HI for the 35delG, compound heterozygosity and other GJB2 mutations by PCR, restriction enzyme based screening, SSCP and sequencing. In all patients, non-progressive hearing impairment varied from moderate to profound involving all frequencies. This study revealed one novel silent mutation (438C/T), three novel gene variants resulting in amino acid substitutions (K112E, T123S, K223R) and two novel HI-related mutations (I82M, 313del14).
Institute of Anthropology and Human Genetics, Molecular Genetics, University of Tübingen, Tübingen, Germany. susankupka@yahoo.de
Susan
S
Kupka
Simone
S
Braun
Susanne
S
Aberle
Birgit
B
Haack
Margret
M
Ebauer
Ulrike
U
Zeissler
Hans-Peter
HP
Zenner
Nikolaus
N
Blin
Markus
M
Pfister
D000293:Adolescent; D000328:Adult; D001483:Base Sequence; D002648:Child; D002675:Child, Preschool; D000072259:Connexin 26; D017630:Connexins / Q000235:genetics*; D004247:DNA / Q000737:chemistry / Q000235:genetics; D004252:DNA Mutational Analysis; D005787:Gene Frequency; D005858:Germany; D006319:Hearing Loss, Sensorineural / Q000235:genetics* / Q000503:physiopathology; D006320:Hearing Tests; D006801:Humans; D007223:Infant; D008875:Middle Aged; D009154:Mutation; D018807:Polymorphism, Single-Stranded Conformational; D017384:Sequence Deletion
D017630:Connexins; C000607042:GJB2 protein, human; D000072259:Connexin 26; D004247:DNA