title: Unique spectrum of GJB2 mutations in Mexico.
abstract: OBJECTIVE
  The aim of this study was to elucidate the involvement of mutations in three relatively common deafness genes in Mexican individuals with non-syndromic hearing loss.
  
  
  METHODS
  We sequenced GJB2 for mutations, screened for two deletions involving GJB6, del(GJB6-D13S1830) and del(GJB6-D13S1854), and for the m.1555A>G mutation in the MTRNR1 gene in 76 (71 simplex and 5 multiplex) unrelated Mexican probands with prelingual non-syndromic hearing loss. Samples were obtained from the Department of Genetics at Instituto Nacional de Rehabilitacion in Mexico City.
  
  
  RESULTS
  Eight previously reported pathogenic variants and two polymorphic variants in GJB2 were identified. The two screened GJB6 deletions and the m.1555A>G mutation were not detected. Eight cases (10.6%) were found to have bi-allelic mutations in GJB2 and six (7.9%) were found to have a monoallelic GJB2 mutation. Of the six monoallelic mutations, one (p.R184Q) was a previously reported autosomal dominant variant. The most frequent pathological allele detected in this population was the c.35delG mutation in the GJB2 gene. The p.V27I polymorphic variant was also detected, with an allele frequency of 0.24. All eight probands with GJB2 mutations had symmetric profound deafness, whereas patients without GJB2 mutations had moderate, severe or profound hearing loss.
  
  
  CONCLUSIONS
  This study shows that GJB2 mutations are an important cause of prelingual deafness in the Mexican population.
authors.affiliation: Departamento de Genetica, Instituto Nacional de Rehabilitacion, Calzada de Mexico Xochimilco No. 289, Colonia Arenal de Guadalupe, Delegacion Tlalpan, Mexico CP 14389, Mexico.
authors.forename: Maria
authors.initials: M
authors.lastname: de la Luz Arenas-Sordo
authors.forename: Ibis
authors.initials: I
authors.lastname: Menendez
authors.forename: Edgar
authors.initials: E
authors.lastname: Hernández-Zamora
authors.forename: Asli
authors.initials: A
authors.lastname: Sirmaci
authors.forename: Diana
authors.initials: D
authors.lastname: Gutiérrez-Tinajero
authors.forename: Molly
authors.initials: M
authors.lastname: McGetrick
authors.forename: Paulina
authors.initials: P
authors.lastname: Murphy-Ruiz
authors.forename: Xolotl
authors.initials: X
authors.lastname: Leyva-Juárez
authors.forename: Fabiola
authors.initials: F
authors.lastname: Huesca-Hernández
authors.forename: Juan
authors.initials: J
authors.lastname: Dominguez-Aburto
authors.forename: Mustafa
authors.initials: M
authors.lastname: Tekin
mesh_terms: D000072259:Connexin 26; D000075302:Connexin 30; D017630:Connexins / Q000235:genetics*; D003638:Deafness / Q000235:genetics; D017353:Gene Deletion; D005787:Gene Frequency; D034381:Hearing Loss / Q000235:genetics*; D006579:Heterozygote; D006801:Humans; D008800:Mexico; D009154:Mutation; D011110:Polymorphism, Genetic
chemical_list: D000075302:Connexin 30; D017630:Connexins; C000607042:GJB2 protein, human; C491020:GJB6 protein, human; D000072259:Connexin 26