title: Correlation between GJB2 mutations and audiological deficits: personal experience.
abstract: Mutations in GJB2 gene are the most common cause of genetic deafness. More than 100 mutations have been described. The aim of this work is to describe the personal experience in genetic hearing loss, investigating the audiological and genetical characteristics of Cx26 deafness and correlating genotype and phenotype. We performed audiological and genetical evaluation in 154 patients affected by non-syndromic deafness of different degree. All patients showed a bilateral symmetrical sensorineural hearing loss. From the genetical analysis 127 probands resulted as negatives while 27 as positives (51.8% homozygous for 35 delG, 14.8% compound heterozygosis and 33.3% single mutation); 7.5% of patients had a mild deafness, 37% moderate, 33.3% severe and 22.2% profound. The c.35 delG mutation was detected in 66.6% of patients. Three mutations were found in compound heterozygosis with 35 delG, six different single mutations already described, and a new mutation S138G were also found. Correlation between genotype and phenotype confirmed the high variability of hearing loss.
authors.affiliation: Ist Clinica ORL, Università Cattolica del Sacro Cuore, Policlinico A Gemelli, Rome, Italy. pmpicciotti@rm.unicatt.it
authors.forename: Pasqualina M
authors.initials: PM
authors.lastname: Picciotti
authors.forename: Roberta
authors.initials: R
authors.lastname: Pietrobono
authors.forename: Giovanni
authors.initials: G
authors.lastname: Neri
authors.forename: Gaetano
authors.initials: G
authors.lastname: Paludetti
authors.forename: Anna Rita
authors.initials: AR
authors.lastname: Fetoni
authors.forename: Francesca
authors.initials: F
authors.lastname: Cianfrone
authors.forename: Maria Grazia
authors.initials: MG
authors.lastname: Pomponi
mesh_terms: D000158:Acoustic Impedance Tests; D000293:Adolescent; D000328:Adult; D000368:Aged; D001299:Audiometry; D001309:Auditory Threshold / Q000502:physiology*; D002648:Child; D002675:Child, Preschool; D015331:Cohort Studies; D000072259:Connexin 26; D017630:Connexins / Q000235:genetics*; D005260:Female; D005838:Genotype; D006312:Hearing Loss, Bilateral / Q000235:genetics*; D006319:Hearing Loss, Sensorineural / Q000235:genetics*; D006801:Humans; D008297:Male; D008875:Middle Aged; D009154:Mutation / Q000235:genetics*; D010641:Phenotype; D055815:Young Adult
chemical_list: D017630:Connexins; C000607042:GJB2 protein, human; D000072259:Connexin 26