Molecular Biology Reports

, Volume 39, Issue 12, pp 10481–10487 | Cite as

Prevalence of GJB2 (CX26) gene mutations in south Iranian patients with autosomal recessive nonsyndromic sensorineural hearing loss

  • Seyed Basir Hashemi
  • Mohamad Javad Ashraf
  • Mohamad Saboori
  • Negar Azarpira
  • Masumeh Darai


Hereditary hearing loss is a genetically heterogeneous disorder. Mutations in connexin 26 (CX26), are a major cause in many countries and are largely dependent on ethnic groups. The purpose of our study was to evaluate the prevalence of GJB2 mutations among affected individuals from south of Iran. Fifty patients presenting with autosomal recessive non-syndromic hearing loss from Fars, province in south of Iran, were studied for mutations in GJB2 gene and screened by direct sequencing. Mutations were detected in 15 out of 50 patients (30 %). Eight different mutations were identified; six of them were previously identified (35delG, V27I M34V, V153I, A149T, V198M). The remaining two alleles, L28I and N169T, were novel variants. The most common mutations were 35delG followed by V153I with an allele frequency of 7 and 6 %, respectively. In this study, 30 % of our subjects were found to have the causative variants or polymorphisms in GJB2 and the c.35delG mutation was the most common cause in our patients. However, more study with larger sample size as well as in vitro functional study for these new variants in Xenopus oocytes is required.


GJB2 Iran Hearing loss Genotype 



This work is the result of the thesis which is done by Mohamad Saboori and supported by Shiraz University of Medical Sciences.


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Copyright information

© Springer Science+Business Media Dordrecht 2012

Authors and Affiliations

  • Seyed Basir Hashemi
    • 1
  • Mohamad Javad Ashraf
    • 2
  • Mohamad Saboori
    • 2
  • Negar Azarpira
    • 3
  • Masumeh Darai
    • 3
  1. 1.Department of OtolaryngologyShiraz University of Medical SciencesShirazIran
  2. 2.Department of PathologyShiraz University of Medical SciencesShirazIran
  3. 3.Transplant Research CenterShiraz University of Medical SciencesShirazIran

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