implicated by this study. Therefore longevity has a large mutational target size; genes affecting life span have variable allelic effects; alleles affecting life span exhibit antagonistic pleiotropy and form epistatic networks ; and sex-specific mutational effects are ubiquitous." Link: http://www.ncbi.nlm.nih.gov/pmc/articles/PMC2912381/ 04 Aug 2010 Some People Have Better Mitochondrial DNA, Part III Permalink