Analysis of mitochondrial DNA gene mutations in hearing loss induced by military noise / 解放军医学杂志

ABSTRACT

Objective To investigate the relationship between mitochondrial DNA gene mutations and the susceptibility to military noise,and to provide a criterion for screening the individuals susceptible to military noise through molecular biology diagnostic method.Methods An investigation of hearing loss was performed among a total of 1032 servicemen including 406 tankers and 626 artillerymen who have endured military noise in their military duty.A total of 122 blood samples were collected,of which 82 samples were collected from susceptible individuals(susceptible group) and 40 from tolerance individuals(tolerance group).DNA was then extracted from the leukocytes of blood samples.The gene fragments of mitochondrial DNA,which might associate with non-syndromal hearing loss,were amplified by polymerase chain reaction(PCR).The PCR products were analyzed by sequencing and contrasting.The gene mutations which were different from the standard sequences of mitochondrial genome were then compared between the susceptible and tolerance groups.Further auditory analysis was performed on those persons who had the gene mutations of hearing loss.Results The gene sequencing revealed there were definite differences in mitochondrial DNA between the susceptible and tolerance groups,and statistically significant difference was found in mitochondrial DNA COII gene T7684C and G7853A mutations between the two groups.Mitochondrial DNA gene mutations were found in the present study,such as A827G,T961insC(heterogeneity),T1005C,T1095C and G7444A,which were reported to be related to deafness in literature.Most of these mutations were detected from the samples of susceptible group,and the others from tolerance group.Conclusion The mitochondrial DNA COII gene T7684C and G7853A mutations might exist in those persons who are susceptible to military noise.