Different mtDNA variants can coexist within a single cell in a state of heteroplasmy, competing for the cellular resources necessary for their replication. In this review, we examine documented cases of selfish mitochondrial DNAs — variants that gain a replication advantage within cells but are detrimental at the cellular level — across a range of eukaryotic species, from humans to bakers yeast. This review discusses hypothetical mechanisms that may promote the proliferation of specific mtDNA variants over others in the heteroplasmic cells. Finally, we suggest that the risk posed by selfish mtDNAs has significantly shaped eukaryotic evolution, leading to the emergence of uniparental inheritance and constraints on mtDNA copy number.
Muravyov et al. (Wed,) studied this question.