Smithsonian Institution, National Museum of Natural History, Department of Anthropology, Washington, DC 20560, USA.
Aging Dis. 2013 Oct 3;4(6):364-80. doi: 10.14336/AD.2013.0400364.
Mitochondria are independent organelles with their own DNA. As a primary function, mitochondria produce the energy for the cell through Oxidative Phosphorylation (OXPHOS) in the Electron Transport Chain (ETC). One of the toxic products of this process is Reactive Oxygen Species (ROS), which can induce oxidative damage in macromolecules like lipids, proteins and DNA. Mitochondrial DNA (mtDNA) is less protected and has fewer reparation mechanisms than nuclear DNA (nDNA), and as such is more exposed to oxidative, mutation-inducing damage. This review analyzes the causes and consequences of mtDNA mutations and their relationship with the aging process. Neurodegenerative diseases, related with the aging, are consequences of mtDNA mutations resulting in a decrease in mitochondrial function. Also described are "mitochondrial diseases", pathologies produced by mtDNA mutations and whose symptoms are related with mitochondrial dysfunction. Finally, mtDNA haplogroups are defined in this review; these groups are important for determination of geographical origin of an individual. Additionally, different haplogroups exhibit variably longevity and risk of certain diseases. mtDNA mutations in aging and haplogroups are of special interest to forensic science research. Therefore this review will help to clarify the key role of mtDNA mutations in these processes and support further research in this area.
线粒体是具有自身 DNA 的独立细胞器。作为主要功能，线粒体通过电子传递链（ETC）中的氧化磷酸化（OXPHOS）为细胞产生能量。这个过程的有毒产物之一是活性氧物种（ROS），它可以诱导脂质、蛋白质和 DNA 等大分子发生氧化损伤。线粒体 DNA（mtDNA）的保护程度低于核 DNA（nDNA），并且修复机制也较少，因此更容易受到氧化和诱变损伤的影响。本篇综述分析了 mtDNA 突变的原因和后果及其与衰老过程的关系。与衰老有关的神经退行性疾病是 mtDNA 突变导致线粒体功能下降的结果。本文还描述了“线粒体疾病”，即由 mtDNA 突变引起的病理学，其症状与线粒体功能障碍有关。最后，本文定义了 mtDNA 单倍群；这些群体对于确定个体的地理起源很重要。此外，不同的单倍群表现出不同的长寿和某些疾病的风险。衰老和单倍群中的 mtDNA 突变是法医学研究的特别关注点。因此，本篇综述将有助于阐明 mtDNA 突变在这些过程中的关键作用，并为该领域的进一步研究提供支持。
