High carrier frequency of the GJB2 mutation (35delG) in the north of Iran.
OBJECTIVE
Mutations in the GJB2 gene are a major cause of autosomal recessive and sporadic non-syndromic hearing loss in many populations. A single mutation of this gene (35delG) accounts for approximately 70% of mutations in Caucasians with a carrier frequency of 2-4% in Europe. This study aims to determine the rate of 35delG carrier frequency in Iran.


METHODS
Genomic DNA was extracted from a total of 550 unaffected unrelated subjects from 4 provinces of Iran following the standard phenol chloroform procedure. The one base pair deletion (35delG) was analysed using a nested PCR procedure; 35delG mutation carriers were subsequently confirmed by sequence analysis. Moreover, using the Binomial probability distribution, we compared the 35delG carrier frequency of Iranian population with the various Middle Eastern and overall European populations.


RESULTS
Of the four populations studied, we found a high carrier frequency of 2.8% in Gilan province in the north of Iran. The overall 35delG carrier frequency was found to be 1.25% in the populations studied (our present and previous data) which is similar to the overall 35delG carrier frequency detected in Middle Eastern populations, but Significantly lower than that identified in European populations.
Chaleshtori
Morteza Hashemzadeh
MH
Cellular and Molecular Research Center, Shahrekord University of Medical Sciences, Shahrekord, Iran. mchalesh@yahoo.com
Farrokhi
Effat
E
Shahrani
Mehrdad
M
Kheiri
Soleiman
S
Dolati
Masoumeh
M
Rad
Laleh Hoghooghi
LH
Pour-Jafari
Hamid
H
Samani
Keihan Ghatreh
KG
Chaleshtori
Katayoon Safa
KS
Crosby
Andrew H
AH
D020029:Base Pairing / Q000235:genetics; D000072259:Connexin 26; D017630:Connexins / Q000235:genetics*; D004586:Electrophoresis; D004591:Electrophoresis, Polyacrylamide Gel; D005060:Europe; D017353:Gene Deletion; D005787:Gene Frequency / Q000235:genetics*; D006580:Genetic Carrier Screening; D006147:Guanine; D034381:Hearing Loss / Q000235:genetics; D006801:Humans; D007492:Iran; D008877:Middle East; D009154:Mutation / Q000235:genetics*; D016133:Polymerase Chain Reaction; D017422:Sequence Analysis, DNA
D017630:Connexins; C000607042:GJB2 protein, human; D000072259:Connexin 26; D006147:Guanine