A range of studies suggest that variations in mitochondrial DNA influence human longevity, which is what we'd expect given the mass of evidence for the importance of mitochondria DNA damage in aging, and the role of mitochondrial function in many age-related diseases. Here, however, is a study showing no statistically identifiable effects resulting from different mitochondrial DNA haplotypes in the old:
Inherited genetic variation of mitochondrial DNA (mtDNA) could account for the missing heritability of human longevity and healthy aging. Here, we show no robust association between common genetic variants of mtDNA and frailty (an "unhealthy aging" phenotype) or mortality in 700, more than 85-year-old, participants of the Newcastle 85+ study. Conflicting data from different populations underscore our conclusion that there is currently no compelling link between inherited mtDNA variants and aging.