Correlation between audiometric data and the 35delG mutation in ten patients.
Mutations in the connexin 26 gene seem to be extremely common in non-syndromic hereditary deafness genesis, especially the 35delG, but there are still only a few studies that describe the audiometric characteristics of patients with these mutations.


OBJECTIVE
to analyze the audiometric characteristics of patients with mutations in the connexin 26 gene in order to outline genotype-phenotype correlation.


METHODS
Tonal audiometries of 33 index cases of non-syndromic sensorineural hearing loss were evaluated and eight affected relatives. Specific molecular tests were carried out to analyze mutations in the connexin 26 gene.


METHODS
Retrospective, cross-sectional study.


RESULTS
A 27.3% prevalence of mutation 35delG was found in the index cases and 12.5% among the relatives affected. In relation to hearing loss degree, 41.5% of the patients were found with profound hearing loss, 39% with severe HL and 19.5% with moderate HL with homozygote and heterozygote patients for the 35delG predominating in the severe-moderate hearing losses.


CONCLUSIONS
Our results suggest that the audiometric data associated with the molecular diagnose of hearing loss helped us to outline a genotype-phenotype correlation in ten patients with 35delG mutation. However, it is still necessary to run multicentric studies to verify the real phenotypic expression in the Brazilian population, as far as the 35delG mutation is concerned.
Belintani Piatto
Vânia
V
PhD, Adjunct Professor - Department of Otorhinolaryngology / Head and Neck Surgery - FAMERP.
Vasques Moreira
Otávio Augusto
OA
5th Year Medical Student - FAMERP.
Orate Menezes da Silva
Magali Aparecida
MA
M.Sc. Head of the Speech and Hearing Therapy Division - Department of Otorhinolaryngology / Head and Neck Surgery - FAMERP.
Victor Maniglia
José
J
Associate Professor - Head of the Department of Otorhinolaryngology / Head and Neck Surgery - FAMERP.
Coimbra Pereira
Márcio
M
M.Sc. Department of Otorhinolaryngology / Head and Neck Surgery - FAMERP.
Sartorato
Edi Lúcia
EL
PhD. Head of the Center for Molecular Biology and Genetic Engineering - CBMEG-UNICAMP; Faculdade de Medicina de São José do Rio Preto, SP - FAMERP.
D000293:Adolescent; D000328:Adult; D001299:Audiometry; D002648:Child; D002675:Child, Preschool; D000072259:Connexin 26; D017630:Connexins / Q000235:genetics*; D003430:Cross-Sectional Studies; D005260:Female; D005838:Genotype; D006319:Hearing Loss, Sensorineural / Q000235:genetics*; D006801:Humans; D008297:Male; D009154:Mutation / Q000235:genetics*; D010641:Phenotype; D012189:Retrospective Studies; D012720:Severity of Illness Index
D017630:Connexins; D000072259:Connexin 26