mtDNA mutations, hearing loss and aminoglycoside treatment in Mexicans

• Autor(a) principal: Meza,G
• Data de Publicação: 2011
• Outros Autores: Torres-Ruíz,NM, Tirado-Gutiérrez,C, Aguilera,P
• Tipo de documento: Artigo
• Idioma: eng
• Título da fonte: Brazilian Journal of Otorhinolaryngology
• Texto Completo: http://old.scielo.br/scielo.php?script=sci_arttext&pid=S1808-86942011000500006
• topic: aminoglycosides; dna; mitochondrial; genes; hearing loss; rna

Streptomycin and aminoglycoside derivatives are commonly used to treat tuberculosis and other stubborn infections; these drugs may alter auditory and/or vestibular function. Mutations in mitochondrial DNA have been associated with hypersensitivity to aminoglycosides; no studies have been conducted in Mexicans, which are very prone to such alterations because aminoglycosides have been prescribed carelessly for many years, irrespective of the ailment to be treated. AIM: We investigated "hot spot" mutations described previously as causing inner ear alterations. METHODS: Hot spot mutations at the 12S rRNA gene and the tRNA Serine (UCN) gene were screened by PCR-RFLP and sequencing in 65 subjects undergoing audiological and vestibular testing. STUDY DESIGN: Experimental. RESULTS: 32 individuals had healthy auditory and vestibular function, whereas 33 subjects had auditory affections. We found none of the previously reported mutations related to aminoglycoside hypersensitivity, or non-syndromic hearing loss. Two hearing-impaired patients that had been treated with streptomycin had the T1189C variant of the mitochondrial 12S rRNA region. CONCLUSION: Mutations related to hearing loss in other ethnic backgrounds were not found in Mexicans. However, the T1189C variant is possibly a putative mutation related to aminoglycoside hypersensitivity and was present in 2 patients.