title: [Screening of the mitochondrial 12S rRNA (MTRNR1) gene in probands with sensorineural hearing loss].
abstract: OBJECTIVE
  We investigated mitochondrial DNA 12S rRNA (MTRNR1) gene mutations as a cause of hearing loss in probands with or without a history of aminoglycoside use.
  
  
  METHODS
  The study included 70 patients (40 females, 30 males; age range 3 to 42 years) with nonsyndromic sensorineural hearing loss. Eleven probands had a history of aminoglycoside use before the onset of hearing loss. All cases were first screened and found to be negative for the GJB2 (connexin 26) gene mutations. The m.1555A>G mutation was screened using the PCR-RFLP technique. The entire 12S rRNA gene was later screened with the PCR-TTGE technique followed by direct sequencing.
  
  
  RESULTS
  Of 11 patients with a history of aminoglycoside use, one patient was found to have the m.1555A>G mutation. Two probands with no history of aminoglycoside use exhibited the m.750A>G polymorphism. No pathogenic base substitutions were detected in the remaining patients.
  
  
  CONCLUSIONS
  Apart from the common aminoglycoside ototoxicity-related DNA change, m.1555A>G, we could not identify a common mitochondrial 12S rRNA mutation associated with hearing loss in Turkey. Screening of larger series may document rare alterations.
authors.affiliation: Department of Pediatric Molecular Pathology and Genetics, Medicine Faculty of Ankara University, Ankara, Turkey.
authors.forename: Yaprak E
authors.initials: YE
authors.lastname: Cirçir
authors.forename: Armağan
authors.initials: A
authors.lastname: Incesulu
authors.forename: Mustafa
authors.initials: M
authors.lastname: Tekin
mesh_terms: D000293:Adolescent; D000328:Adult; D002648:Child; D002675:Child, Preschool; D000072259:Connexin 26; D017630:Connexins; D005260:Female; D050259:Genes, Mitochondrial / Q000235:genetics*; D020022:Genetic Predisposition to Disease; D006319:Hearing Loss, Sensorineural / Q000235:genetics*; D006801:Humans; D008297:Male; D009154:Mutation; D016133:Polymerase Chain Reaction; D012150:Polymorphism, Restriction Fragment Length; D012335:RNA, Ribosomal / Q000032:analysis; D014421:Turkey; D044465:White People / Q000235:genetics
chemical_list: D017630:Connexins; C000607042:GJB2 protein, human; D012335:RNA, Ribosomal; C075526:RNA, ribosomal, 12S; D000072259:Connexin 26