title: Molecular approach of auditory neuropathy.
abstract: BACKGROUND
  Mutations in the otoferlin gene are responsible for auditory neuropathy.
  
  
  OBJECTIVE
  To investigate the prevalence of mutations in the mutations in the otoferlin gene in patients with and without auditory neuropathy.
  
  
  METHODS
  This original cross-sectional case study evaluated 16 index cases with auditory neuropathy, 13 patients with sensorineural hearing loss, and 20 normal-hearing subjects. DNA was extracted from peripheral blood leukocytes, and the mutations in the otoferlin gene sites were amplified by polymerase chain reaction/restriction fragment length polymorphism.
  
  
  RESULTS
  The 16 index cases included nine (56%) females and seven (44%) males. The 13 deaf patients comprised seven (54%) males and six (46%) females. Among the 20 normal-hearing subjects, 13 (65%) were males and seven were (35%) females. Thirteen (81%) index cases had wild-type genotype (AA) and three (19%) had the heterozygous AG genotype for IVS8-2A-G (intron 8) mutation. The 5473C-G (exon 44) mutation was found in a heterozygous state (CG) in seven (44%) index cases and nine (56%) had the wild-type allele (CC). Of these mutants, two (25%) were compound heterozygotes for the mutations found in intron 8 and exon 44. All patients with sensorineural hearing loss and normal-hearing individuals did not have mutations (100%).
  
  
  CONCLUSIONS
  There are differences at the molecular level in patients with and without auditory neuropathy.
authors.affiliation: Department of Otorhinolaryngology and Head and Neck Surgery, Faculdade de Medicina de São José do Rio Preto (FAMERP), São José do Rio Preto, SP, Brazil.
authors.forename: Magali Aparecida Orate Menezes da
authors.initials: MA
authors.lastname: Silva
authors.affiliation: Department of Anatomy, Faculdade de Medicina de São José do Rio Preto (FAMERP), São José do Rio Preto, SP, Brazil. Electronic address: vbpiatto@gmail.com.
authors.forename: Vânia Belintani
authors.initials: VB
authors.lastname: Piatto
authors.affiliation: Department of Otorhinolaryngology and Head and Neck Surgery, Faculdade de Medicina de São José do Rio Preto (FAMERP), São José do Rio Preto, SP, Brazil.
authors.forename: Jose Victor
authors.initials: JV
authors.lastname: Maniglia
mesh_terms: D000293:Adolescent; D000328:Adult; D000368:Aged; D016022:Case-Control Studies; D002648:Child; D003430:Cross-Sectional Studies; D004252:DNA Mutational Analysis; D003939:Diagnostic Techniques, Otological; D005260:Female; D005838:Genotype; D006313:Hearing Loss, Central / Q000235:genetics*; D006319:Hearing Loss, Sensorineural / Q000235:genetics; D006801:Humans; D008297:Male; D008565:Membrane Proteins / Q000235:genetics*; D008875:Middle Aged; D009154:Mutation; D016133:Polymerase Chain Reaction; D012150:Polymorphism, Restriction Fragment Length; D055815:Young Adult
chemical_list: D008565:Membrane Proteins; C118457:OTOF protein, human
keywords: Biologia molecular; Deafness; Genes; Molecular biology; Mutation; Mutação; Surdez