GJB2 and mitochondrial A1555G gene mutations in nonsyndromic profound hearing loss and carrier frequencies in healthy individuals.
This study aimed to assess mutations in GJB2 gene (connexin 26), as well as A1555G mitochondrial mutation in both the patients with profound genetic nonsyndromic hearing loss and healthy controls. Ninety-five patients with profound hearing loss (>90 dB) and 67 healthy controls were included. All patients had genetic nonsyndromic hearing loss. Molecular analyses were performed for connexin 26 (35delG, M34T, L90P, R184P, delE120, 167delT, 235delC and IVS1+1 A-->G) mutations, and for mitochondrial A1555G mutation. Twenty-two connexin 26 mutations were found in 14.7% of the patients, which were 35delG, R184P, del120E and IVS1+1 A-->G. Mitochondrial A1555G mutation was not encountered. The most common GJB2 gene mutation was 35delG, which was followed by del120E, IVS1+1 A-->G and R184P, and 14.3% of the patients segregated with DFNB1. In consanguineous marriages, the most common mutation was 35delG. The carrier frequency for 35delG mutation was 1.4% in the controls. 35delG and del120E populations, seems the most common connexin 26 mutations that cause genetic nonsyndromic hearing loss in this country. Nonsyndromic hearing loss mostly shows DFNB1 form of segregation.
Department of Otolaryngology, Faculty of Medicine, Gazi University, TR-06510 Besevler, Ankara, Turkey.
Elif
E
Baysal
Yildirim A
YA
Bayazit
Serdar
S
Ceylaner
Necat
N
Alatas
Buket
B
Donmez
Gulay
G
Ceylaner
Imran
I
San
Baki
B
Korkmaz
Akin
A
Yilmaz
Adnan
A
Menevse
Senay
S
Altunyay
Bulent
B
Gunduz
Nebil
N
Goksu
Ahmet
A
Arslan
Abdullah
A
Ekmekci
D000293:Adolescent; D000328:Adult; D016022:Case-Control Studies; D002648:Child; D002675:Child, Preschool; D000072259:Connexin 26; D017630:Connexins / Q000235:genetics*; D004272:DNA, Mitochondrial / Q000235:genetics; D003638:Deafness / Q000235:genetics*; D005260:Female; D005787:Gene Frequency; D050259:Genes, Mitochondrial; D006579:Heterozygote; D006801:Humans; D007223:Infant; D008297:Male; D008875:Middle Aged; D009154:Mutation
D017630:Connexins; D004272:DNA, Mitochondrial; C000607042:GJB2 protein, human; D000072259:Connexin 26