title: Mitochondrial non-syndromic sensorineural hearing loss: a clinical, audiological and pathological study from Italy, and revision of the literature.
abstract: Over the last decade, a number of distinct mutations in the mtDNA (mitochondrial DNA) have been found to be associated with both syndromic and non-syndromic forms of hearing impairment. Their real incidence as a cause of deafness is poorly understood and generally underestimated. Among the known mtDNA mutations, the A1555G mutation in the 12S gene has been identified to be one of the most common genetic cause of deafness, and it has been described to be both associated to non-syndromic progressive SNHL (sensorineural hearing loss) and to aminoglycoside-induced SNHL. In the present study, we have investigated the presence of mtDNA alterations in patients affected by idiopathic non-syndromic SNHL, both familiar and sporadic, in order to evaluate the frequency of mtDNA alterations as a cause of deafness and to describe the audiological manifestations of mitochondrial non-syndromic SNHL. In agreement with previous studies, we found the A1555G mutation to be responsible for a relevant percentage (5.4%) of cases affected with isolated idiopathic sensorineural hearing impairment.
authors.affiliation: Division of ENT, Department of Neuroscience, University of Pisa, Via Savi 10, Pisa, 56126, Italy. s.berrettini@med.unipi.it
authors.forename: Stefano
authors.initials: S
authors.lastname: Berrettini
authors.forename: Francesca
authors.initials: F
authors.lastname: Forli
authors.forename: Susanna
authors.initials: S
authors.lastname: Passetti
authors.forename: Anna
authors.initials: A
authors.lastname: Rocchi
authors.forename: Luca
authors.initials: L
authors.lastname: Pollina
authors.forename: Denise
authors.initials: D
authors.lastname: Cecchetti
authors.forename: Michelangelo
authors.initials: M
authors.lastname: Mancuso
authors.forename: Gabriele
authors.initials: G
authors.lastname: Siciliano
mesh_terms: D000328:Adult; D000368:Aged; D004272:DNA, Mitochondrial / Q000235:genetics / Q000378:metabolism; D003638:Deafness / Q000235:genetics / Q000378:metabolism / Q000473:pathology; D005260:Female; D006319:Hearing Loss, Sensorineural / Q000235:genetics / Q000378:metabolism* / Q000473:pathology*; D006801:Humans; D008297:Male; D008875:Middle Aged; D008928:Mitochondria / Q000235:genetics / Q000378:metabolism*; D010375:Pedigree; D017354:Point Mutation
chemical_list: D004272:DNA, Mitochondrial