“…Other authors have remarked that mitochondria may have a significant but unknown biological function other than energy production (Nagao et al, 1998). In fact, little is known about the exact role and function of the mtDNA (Thornburn et al, 2001) and little is known about the significance of altering the match between nuclear and mitochondrial complements (Bonnicksen, 1998;Bowles et al, 2007;St John et al, 2004;Poulton et al, 2006). Although perhaps hypothetical, the mtDNA may influence nuclear gene expression and this, in turn, may influence essential characteristics of the resulting child (Szebik, 1999;Parens and Juengst, 2001).…”