Maliarchuk B A
Mol Biol (Mosk). 1995 Mar-Apr;29(2):281-6.
It is demonstrated that human mitochondrial DNA (mtDNA) exhibits the chain asymmetry of TG and CA dinucleotide frequencies presumably due to replicative and postreplicative methylation of CG sites of mtDNA and specific mitochondrial genome replication. The analysis of population data on human mtDNA variability has revealed two mutation flows: one intense G-->A and C-->T and less intense A-->G, T-->C and C-->G flows; the letter results in formation of G,C-enriched mtDNA palindromic structures and CG dinucleotides. The interaction of these two mutation flows through the system of DNA methylation/deamination enables to consider the above mentioned processes as a mechanism of DNA evolution maintaining certain level of mtDNA diversity in human populations.
研究表明，人类线粒体DNA（mtDNA）表现出TG和CA二核苷酸频率的链不对称性，这可能是由于mtDNA的CG位点的复制和复制后甲基化以及特定的线粒体基因组复制所致。对人类mtDNA变异性的群体数据进行分析后发现了两种突变流：一种是强烈的G→A和C→T流，以及较弱的A→G、T→C和C→G流；后者导致富含G、C的mtDNA回文结构和CG二核苷酸的形成。这两种突变流通过DNA甲基化/脱氨基系统的相互作用，使得上述过程被认为是一种在人类群体中维持mtDNA一定多样性水平的DNA进化机制。
