Epidemiological Investigation And Analysis Of Mitochondrial DNA Gene Mutations In Hearing Loss Induced By Military Noise

Objective:Considerable research in the past displays that there is a close association between hearing loss and mitochondrial DNA gene mutations.Based on this,to investigate the relationship of associating mitochondrial DNA gene mutations with the susceptivity of military noise induced hearing loss and provide evidence for searching path to discover noise susceptible through molecular biology and to search methods to prevent and cure military noise induced hearing loss.Methods:Investigating about hearing loss in 406 Tank soldiers and 626 artillery men, 1032 officers and soldiers in all,suffered military noise in yunnan province.Blood samples were collected from the group,including 82 susceptible and 40 tolerance,122 in all.DNA was extracted from the leukocytes in blood samples.The gene fragments of mitochondrial DNA associating with hearing loss strongly,such as 12S rRNA, tRNA Val,16S rRNA,COⅠ,S(UCN),tRNA Asp and COⅡ,were amplified by polymerase chain reaction(PCR).PCR products were analyzed by sequencing and contrasting.The results' statistics analysis was done by SPSS 11.5 software.Results:PCR amplification products had specificity strap in all samples,like expected.Sequencing discovered that there were some differences in mitochondrial DNA between susceptible and tolerance groups.We found 76 basyl changes,41 only in susceptible group,17 only in tolerance group,29 never had been reported among the total.Mitochondrial DNA COⅡgene T7684C and G7853A mutations were found in susceptible group merely,and had statistics difference between two groups(P＜0.05).Mitochondrial DNA gene mutations are probably related to deafness in literature,such as A827G,T961insC(heterogeneity),T1005C,T1095C,G7444A, were found in the study,most of which distributed in experimental group,others in control group.Conclusions:The mitochondrial DNA COⅡgene T7684C and G7853A mutations is probably associated with susceptivity of military noise induced hearing loss,maybe the tag SNP of military noise induced hearing loss,we suppose that the person who have the two basyl changes will have hearing loss more easily after suffering military noise,which is worth to studying more.The single mutation in the mitochondrial DNA gene connected with mitochondrial haplotype,nuclear gene and environmental factor,may play an interaction role in influencing the phenotype of deafness,and the different deafness type may have the same gene mutations.