title: Relationship Between Patients with Clinical Auditory Neuropathy Spectrum Disorder and Mutations in Gjb2 Gene.
abstract: The auditory neuropathy is a condition which there is a dyssynchrony in the nerve conduction of the auditory nerve fibers. There is no evidence about the relationship between patients with clinical auditory neuropathy spectrum disorder and mutations in GJB2 gene. There are only two studies about this topic in the medical literature. Connexin 26 (GJB2 gene) mutations are common causes of genetic deafness in many populations and we also being reported in subjects with auditory neuropathy.
  
  
  OBJECTIVE
  To analyze the pattern of clinical relationship between patients with clinical diagnosis with auditory neuropathy spectrum disorder and GJB2 gene.
  
  
  METHODS
  Study Design - Retrospective analysis and genetic evaluation. Setting - Tertiary referral center. Subjects - 40 patients with Auditory Neuropathy Spectrum Disorder. Intervention - Clinical information and genetic evaluation (GJB2 gene) were analyzed.
  
  
  RESULTS
  Biallelic mutations that accounted for hearing loss (HL) were found in three patients, both with c.35delG mutation in homozygous state. The splice site mutation IVS1+1G>A was detected in heterozygous state in one individual. However, since the second mutant allele was not identified, it was not possible to establish its correlation with the phenotype.
  
  
  CONCLUSIONS
  Mutations in GJB2 gene mutations were found in 7.5% of the patients with ANSD. We found no relationship between patients with clinical auditory neuropathy spectrum disorder and mutations in GJB2 gene (p>0.05).
authors.affiliation: Otologist, Otology, Audiology and Implantable Ear Prostheses, Unicamp, Sao Paulo, Brazil.
authors.forename: Guilherme M
authors.initials: GM
authors.lastname: de Carvalho
authors.affiliation: Human Molecular Genetics Laboratory, Molecular Biology and Genetic Engineering Center, CBMEG, Unicamp, Sao Paulo, Brazil.
authors.forename: Priscila
authors.initials: P
authors.lastname: Z Ramos
authors.affiliation: Otologist, Otology, Audiology and Implantable Ear Prostheses, Unicamp, Sao Paulo, Brazil.
authors.forename: Arthur
authors.initials: A
authors.lastname: M Castilho
authors.affiliation: Otologist, Otology, Audiology and Implantable Ear Prostheses, Unicamp, Sao Paulo, Brazil.
authors.forename: Alexandre
authors.initials: A
authors.lastname: C Guimarães
authors.affiliation: Molecular Biology and Genetic Engineering Center, CBMEG, Unicamp, Sao Paulo, Brazil.
authors.forename: Edi
authors.initials: E
authors.lastname: L Sartorato
keywords: Auditory neuropathy spectrum disorder; Evoked auditory brainstem response; GJB2; Hearing loss; Otoacoustic emissions