Mitochondria are generally regarded as having evolved symbiotically from ancient bacteria and eukaryotic cells. As the energy factories of cells, their genomes are independent.Mitochondria rapidly accumulate mutations throughout a lifetime, potentially acting as a molecular clock for aging and disease.
In this study, researchers profiled mitochondrial RNA across 47 human tissues from 838 individuals, revealing rapid development of clonal mosaicism with two distinct tissue-specific aging signatures. Researchers utilized rare variation identification techniques to conduct in-depth extraction of 11,802 low-frequency variation data of mitochondrial transcriptomes from international public databases (covering 47 types of tissues from 838 individuals), systematically mapping a human tissue-specific mitochondrial mutation map, and revealing the “dual-phase” clock pattern of mitochondrial mutations accumulating with age.
It was proposed that mitochondria encode organ aging through two different modes – random mutation diffusion in proliferative renewal tissues and deterministic damage hotspots in terminally differentiated tissues. In this study, the mitochondrial genome sequencing of 8 cases of testicular tissues was completed by the SURFSeq 5000 platform of GeneMind, achieving the verification of mitochondrial mutation hotspots.
