Mitochondrial DNA (mtDNA) mutations/deletions are considered to be associated with the
development of age-related hearing loss (AHL). We assessed the role of accumulation of
mtDNA mutations in the development of AHL using PolgD257A knock-in mouse, which
exhibited increased spontaneous mtDNA mutation rates during aging and showed
accelerated aging primarily due to increased apoptosis. They exhibited moderate hearing
loss and degeneration of the hair cells, spiral ganglion cells and stria vascularis by 9 month …