Table of Contents
International Journal of Medical Genetics
Volume 2014, Article ID 856313, 8 pages
Research Article

Evidence for Central Asian Origin of the p.Val27Ile Variant in the GJB2 Gene

Departamento de Neurociencias, Instituto Nacional de Rehabilitación, Calzada México-Xochimilco 289, Colonia Arenal de Guadalupe, 14389 México, DF, Mexico

Received 29 August 2014; Accepted 9 November 2014; Published 7 December 2014

Academic Editor: Nejat Akar

Copyright © 2014 Guille García Sánchez et al. This is an open access article distributed under the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited.


The mutations in the GJB2 gene are the most common cause of nonsyndromic hearing impairment and they are associated with the population’s ethnic background. The p.Val27Ile is frequent in both Asia and America. In this retrospective study, we report the findings from the GJB2 screening and the audiological exams conducted on 125 Mexican mestizo patients with non-syndromic hearing impairment; they were treated at the Instituto Nacional de Rehabilitacion in Mexico City. The most frequent audiometric findings were bilateral, symmetrical, and profound hearing impairment. The allele frequencies in the GJB2 screening were p.Val27Ile 15%, other mutations 5%, and wild type 80%. We found no correlation between GJB2 genotype and auditory phenotype. The high allele frequency of p.Val27Ile was a very interesting finding. Our research suggests that p.Val27Ile arose in an ancient common ancestor who lived in Altai Republic and then the polymorphism was brought to America by its first inhabitants, the Amerindians. These results enhance our understanding of the peopling of the America, which remains unresolved.