title: A novel dominant missense mutation--D179N--in the GJB2 gene (Connexin 26) associated with non-syndromic hearing loss.
abstract: Mutations of the GJB2 gene, encoding Connexin 26, are the most common cause of hereditary congenital hearing loss in many countries, and account for up to 50% of cases of autosomal-recessive non-syndromic deafness. By contrast, only a few GJB2 mutations have been reported to cause an autosomal-dominant form of non-syndromic deafness. We report on a family from southern Italy in whom dominant, non-syndromic, post-lingual hearing loss is associated with a novel missense mutation in the GJB2 gene. Direct sequencing of the gene showed a heterozygous G-->A transition at nucleotide 535, resulting in an aspartic acid to asparagine amino acid substitution at codon 179 (D179N). This mutation occurred in the second extracellular domain (EC2), which would seem to be very important for connexon-connexon interaction.
authors.affiliation: Dipartimento di Medicina di Laboratorio-Laboratorio di Genetica Medica, A.O. Istituti Clinici di Perfezionamento, Milan, Italy.
authors.forename: P
authors.initials: P
authors.lastname: Primignani
authors.forename: P
authors.initials: P
authors.lastname: Castorina
authors.forename: F
authors.initials: F
authors.lastname: Sironi
authors.forename: C
authors.initials: C
authors.lastname: Curcio
authors.forename: U
authors.initials: U
authors.lastname: Ambrosetti
authors.forename: D A
authors.initials: DA
authors.lastname: Coviello
mesh_terms: D019943:Amino Acid Substitution; D000072259:Connexin 26; D000075302:Connexin 30; D017630:Connexins / Q000235:genetics* / Q000378:metabolism; D004252:DNA Mutational Analysis; D005260:Female; D005799:Genes, Dominant; D034381:Hearing Loss / Q000235:genetics* / Q000503:physiopathology; D006801:Humans; D008297:Male; D020125:Mutation, Missense; D010375:Pedigree
chemical_list: D000075302:Connexin 30; D017630:Connexins; C000607042:GJB2 protein, human; C491020:GJB6 protein, human; D000072259:Connexin 26