title: Two novel compound heterozygous families with a trimutation in the GJB2 gene causing sensorineural hearing loss.
abstract: BACKGROUND
  Sensorineural hearing loss (SNHL) is a genetically heterogeneous disease. GJB2 gene mutations seem to be the most frequent cause of hereditary hearing impairment in several populations. There is variability in the mutations in the GJB2 gene worldwide; this remarks the influence of ethnic background in SNHL.
  
  
  OBJECTIVE
  To describe the presence of two trimutations in the GJB2 gene in two Mexican families with hereditary SNHL.
  
  
  METHODS
  Two unrelated Mexican families with prelingual SNHL were included in the study. Analysis of the GJB2 gene through PCR and DNA direct sequencing analysis was performed in all members of the families and in 100 normal controls.
  
  
  RESULTS
  Affected member of the family 1 showed the trimutation p.S19R/p.R32S/p.E47*, whereas affected members of the family 2 showed the trimutation p.F31I/p.W44*/p.V84M. Parents of both families were heterozygous with normal audition.
  
  
  CONCLUSIONS
  We found a novel mutation in the GJB2 gene and two trimutations with SNHL not previously reported. This remarks the complexity in the pattern of mutations in the GJB2 gene in SNHL and enriches the spectrum of the type of molecular defects in the GJB2 gene.
authors.forename: Mirna
authors.initials: M
authors.lastname: Martínez-Saucedo
authors.affiliation: Servicio de Genética, Facultad de Medicina, Hospital General de Mexico, Universidad Nacional Autonoma de Mexico, Edo. México, Mexico.
authors.forename: Martínez-Saucedo
authors.initials: MS
authors.lastname: Mirna
authors.forename: María del Refugio
authors.initials: Mdel R
authors.lastname: Rivera-Vega
authors.affiliation: Servicio de Genética, Facultad de Medicina, Hospital General de Mexico, Universidad Nacional Autonoma de Mexico, Edo. México, Mexico.
authors.forename: Rivera-Vega
authors.initials: RV
authors.lastname: María Del Refugio
authors.forename: María
authors.initials: M
authors.lastname: Gonzalez--Huerta Luz
authors.affiliation: Servicio de Genética, Facultad de Medicina, Hospital General de Mexico, Universidad Nacional Autonoma de Mexico, Edo. México, Mexico.
authors.forename: Gonzalez-Huerta Luz
authors.initials: GH
authors.lastname: María
authors.forename: Héctor
authors.initials: H
authors.lastname: Urueta-Cuellar
authors.affiliation: Servicio de Genética, Facultad de Medicina, Hospital General de Mexico, Universidad Nacional Autonoma de Mexico, Edo. México, Mexico.
authors.forename: Urueta-Cuellar
authors.initials: UC
authors.lastname: Héctor
authors.forename: Jaime
authors.initials: J
authors.lastname: Toral-López
authors.affiliation: Departamento de Genética Médica, Centro Médico Ecatepec, ISSEMYM, Edo. México, Mexico.
authors.forename: Toral-López
authors.initials: TL
authors.lastname: Jaime
authors.forename: Pedro
authors.initials: P
authors.lastname: Berruecos-Villalobos
authors.affiliation: Servicio de Audiología, Hospital General de México, Facultad de Medicina, Universidad Nacional Autónoma de México, Mexico.
authors.forename: Berruecos-Villalobos
authors.initials: BV
authors.lastname: Pedro
authors.affiliation: Servicio de Genética, Facultad de Medicina, Hospital General de Mexico, Universidad Nacional Autonoma de Mexico, Edo. México, Mexico. Electronic address: sergiocuevasunam@gmail.com.
authors.forename: Sergio
authors.initials: S
authors.lastname: Cuevas-Covarrubias
authors.forename: Cuevas-Covarrubias
authors.initials: CC
authors.lastname: Sergio
mesh_terms: D000328:Adult; D000072259:Connexin 26; D017630:Connexins / Q000235:genetics*; D005260:Female; D006319:Hearing Loss, Sensorineural / Q000235:genetics*; D006801:Humans; D008297:Male; D008800:Mexico; D009154:Mutation; D010375:Pedigree; D055815:Young Adult
chemical_list: D017630:Connexins; C000607042:GJB2 protein, human; D000072259:Connexin 26
keywords: Connexins; GJB2 gene; Gene mutations; Hypoacusia