Most researchers focused on methylation of genomic DNA, while methylation of mitochondrial DNA (mtDNA) is rarely tauched, and there is still controversy about the existence of mtDNA methylation. The study of cytosine methylation in mtDNA is limited. The mtDNA was recently found to exist CpG hypomethylation, and more studies provided evidence that mtDNA methylation plays an important role in mitochondrial gene regulation. In present review, we will overview recent studies of mitochondrial DNA methylation and potential influencing factors in diseases that are involved in mtDNA methylation. Thus, the further studies on mtDNA methylation will provide more evidence to explain the mechanism of mtDNA methylation and an advantageous approach for human clinical diagnosis and prevention.
Keywords: Methylation; Mitochondrial DNA.