title: Two novel missense mutations in the connexin 26 gene in Turkish patients with nonsyndromic hearing loss.
abstract: Most nonsyndromic hearing losses are caused by mutations in the GJB2 gene, and studies have revealed that the forms and frequencies of these mutations are largely dependent on ethnic origin. In the present study, we aimed to characterize the mutation profiles of 151 patients with hearing loss in Turkey. The entire coding region of the GJB2 was directly sequenced in all patients. We found 35 (23.2%) individuals carrying GJB2 mutations. Seven different mutations were identified, five of which were previously known (35delG, delE120, R184P, M163V, L90P), the remaining two being novel variants (M34V, L205V). The most common mutation was 35delG followed by delE120. The 35delG mutation was homozygous in 22 cases (14.5%) and heterozygous in 4 cases (2.6%). Compound heterozygosity for 35delG was also observed. The delE120 mutation was found in three patients in homozygous form. A homozygous L90P and heterozygous mutations M163V and M34V were found in single cases.
authors: Department of Medical Biology and Genetics, Faculty of Medicine, Gazi University, Besevler, 06510 Ankara, Turkey. akinyilmaz2002@yahoo.com
authors: Akin
authors: A
authors: Yilmaz
authors: Sevda
authors: S
authors: Menevse
authors: Yildirim
authors: Y
authors: Bayazit
authors: Recep
authors: R
authors: Karamert
authors: Volkan
authors: V
authors: Ergin
authors: Adnan
authors: A
authors: Menevse
mesh_terms: D000595:Amino Acid Sequence; D001483:Base Sequence; D000072259:Connexin 26; D017630:Connexins / Q000235:genetics*; D004252:DNA Mutational Analysis; D005787:Gene Frequency; D005820:Genetic Testing; D005838:Genotype; D034381:Hearing Loss / Q000235:genetics*; D006801:Humans; D008969:Molecular Sequence Data; D020125:Mutation, Missense / Q000502:physiology; D014421:Turkey
chemical_list: D017630:Connexins; C000607042:GJB2 protein, human; D000072259:Connexin 26