Cochlear mitochondrial DNA3867bp deletion in aged mice.
OBJECTIVE
To study the status of cochlear mitochondrial DNA (mtDNA) and to determine the location of mtDNA deletion in aged mice.


METHODS
We detected cochlear mtDNA in 2, 7 - 10 and 17 - 19 month old mice by nested polymerase chain reaction (PCR) and DNA sequencing.


RESULTS
mtDNA3867bp deletions were found in the cochleae of aged mice. The deletion occurred within nt9103-nt12970 and were flanked by 15 base pair direct repeats. Comparing the incidence of mtDNA3867bp deletions, 17 - 19 month old mice (7/8) were significantly higher than 7 - 10 month old mice (4/16). The deletion was not observed in 2 month old mice (0/7). The ratio of deleted mtDNA/total mtDNA in 17 - 19 month old mice was higher than in 7 - 10 month old mice (P < 0.001).


CONCLUSIONS
Cochlear mtDNA 3867bp deletion in aged mice may be related to presbycusis.
Zhang
Xinxin
X
Department of Otolaryngology, PLA General Hospital, Beijing 100853, China.
Han
Dongyi
D
Ding
Dalian
D
Dai
Pu
P
Yang
Weiyan
W
Jiang
Sichang
S
Salvi
Richard J
RJ
D000375:Aging / Q000235:genetics*; D000818:Animals; D001483:Base Sequence; D003051:Cochlea / Q000378:metabolism*; D004272:DNA, Mitochondrial / Q000032:analysis / Q000235:genetics*; D051379:Mice; D008969:Molecular Sequence Data; D010085:Oxidative Phosphorylation; D011304:Presbycusis / Q000209:etiology*; D017384:Sequence Deletion
D004272:DNA, Mitochondrial