A different sequence change, in the mitochondrial tRNA gene, has been proposed as a candidate mutation in the sensorineurnal hearing loss. The purpose of current study is to identify the association between the noise-induced sensorineurnal hearing loss and the A to G mutation at nucleotide 3243 of mitochondrial DNA.

Subjects were established by history and chart review, and audiological and clinical data were obtained. Blood was sampled from 101 controls, 50 noise-induced hearing loss, and 12 sensorineural deafness. The DNA of these individuals was extracted, and mitochondrial genome was analyzed by polymerase chain reaction. Subsequently, the coding sequence of mitochondrial genome was sequenced, and compared to the normal sequence, and all sequence variations were analyzed by restriction endonuclease ApaI.

Mitochondrial DNA mutation (3243A->G) was not detected by polymerase chain reaction (PCR) in any patients with noise-induced hearing loss, sensorineural hearing loss, and normal control without hearing loss in Koreans. The DNA sequencing of PCR products did not revealed an A to G substitution at nucleotide 3243 of mitochondrial DNA.

The noise-induced sensorineural hearing loss was not associated with mitochondrial DNA mutation (3243A->G).