GJB2 mutations in mongolia: Complex alleles, low frequency, and reduced fitness of the deaf

Mustafa Tekin, Xia Juan Xia, Radnaabazar Erdenetungalag, Filiz Basak Cengiz, Thomas W. White, Janchiv Radnaabazar, Begzsuren Dangaasuren, Hakki Tastan, Walter E. Nance, Arti Pandya

Research output: Contribution to journalArticlepeer-review

48 Scopus citations


We screened the GJB2 gene for mutations in 534 (108 multiplex and 426 simplex) probands with non-syndromic sensorineural deafness, who were ascertained through the only residential school for the deaf in Mongolia, and in 217 hearing controls. Twenty different alleles, including four novel changes, were identified. Biallelic GJB2 mutations were found in 4.5% of the deaf probands (8.3% in multiplex, 3.5% in simplex). The most common mutations were c.IVS1 + 1G > A (c.-3201G > A) and c.235delC with allele frequencies of 3.5% and 1.5%, respectively. The c.IVS1 + 1G > A mutation appears to have diverse origins based on associated multiple haplotypes. The p.V27I and p.E114G variants were frequently detected in both deaf probands and hearing controls. The p.E114G variant was always in cis with the p.V27I variant. Although in vitro experiments using Xenopus oocytes have suggested that p.[V27I;E114G] disturbs the gap junction function of Cx26, the equal distribution of this complex allele in both deaf probands and hearing controls makes it a less likely cause of profound congenital deafness. We found a lower frequency of assortative mating (37.5%) and decreased genetic fitness (62%) of the deaf in Mongolia as compared to the western populations, which provides an explanation for lower frequency of GJB2 deafness in Mongolia.

Original languageEnglish (US)
Pages (from-to)155-164
Number of pages10
JournalAnnals of Human Genetics
Issue number2
StatePublished - Mar 2010


  • Assortative mating
  • Deafness
  • GJB2
  • Hearing loss
  • Mongolia

ASJC Scopus subject areas

  • Genetics(clinical)
  • Genetics


Dive into the research topics of 'GJB2 mutations in mongolia: Complex alleles, low frequency, and reduced fitness of the deaf'. Together they form a unique fingerprint.

Cite this