The co-occurrence of mtDNA mutations on different oxidative phosphorylation subunits, not detected by haplogroup analysis, affects human longevity and is population-specific. Nicola Raule, Federica Sevini, Shengting Li, Annalaura Barbieri, Federica Tallaro, Laura Lomartire, Dario Vianello, Alberto Montesanto, Jukka S. Moilanen, Vladyslav Bezrukov, Helene Blanche, Antti Hervonen, Kaare Christensen, Luca Deiana, Efstathios S. Gonos, Tom B. L. Kirkwood, Peter Kristensen, Alberta Leon, Pier Giuseppe Pelicci Michel Poulain, Irene M. Rea, Jose Remacle Jean Marie Robine Stefan Schreiber Ewa Sikora Peternella Eline Slagboom Liana Spazzafumo Maria Antonietta Stazi Olivier Toussaint James W. Vaupel Giuseppina Kari Majamaa Markus Perola Thomas E. Johnson Lars Bolund Huanming Yang Giuseppe Passarino and Claudio Franceschi.

To re-examine the correlation between mtDNA variability and longevity, we examined mtDNAs from samples obtained from over 2200 ultranonagenarians (and an equal number of controls) collected within the framework of the GEHA EU project. The samples were categorized by high-resolution classification while about 1300 mtDNA molecules (650 ultranonagenarians and an equal number of controls) were completely sequenced. Sequences made it possible to evaluate for the first time the cumulative effects of specific concomitant mtDNA mutations including those that per se have a low or very low impact. In particular, the analysis of the mutations occurring in different OXPHOS complexes showed a complex scenario with a different mutation burden in 90+ subjects with respect to controls. These findings suggested that mutations in subunits of the OXPHOS complex I had a beneficial effect on longevity while the simultaneous presence of mutations in complex I and III (which also occurs in J subhaplogroups involved in LHON) and in complex I and V seemed to be detrimental, likely explaining previous contradictory results. On the whole, our study, which goes beyond haplogroup analysis, suggests that mitochondrial DNA variation does affect human longevity, but its effect is heavily influenced by the interaction between mutations concomitantly occurring on different mtDNA genes.

Biophysics and Biocomplexity and Department of Experimental Pathology, C.I.G. Interdepartmental Centre L. Galvani for Integrated Studies on Bioinformatics, University of Bologna, Bologna, Italy. BGI Shenzhen, Shenzhen, China. Department of Cell Biology, University of Calabria, Rende, Italy. Institute of Clinical Medicine, University of Oulu, Oulu University Hospital and MRC Oulu, Oulu, Finland. Institute of Gerontology, Kiev, Ukraine. Centre Polymorphisme Humaine, Fondation Jean Dausset, Paris, France. University of Tampere, Tampere, Finland. Institute of Public Health, University of Southern Denmark, Odense Denmark. University of Sassari, Sassari Italy. National Hellenic Research Foundation, Athens Greece. School of Clinical Medical Sciences Gerontology Henry Wellcome University of Newcastle upon Tyne Newcastle upon Tyne NEBZ UK. University of Aarhus Aarhus Denmark. Research & Innovation Soc.Coop. a r.l., Padova Italy. Research Centre of Demographic Management for Public UCLG AP Louvain-la-Neuve Belgium The Queens University Belfast Belfast BTNN UK Eppendorf Array Technologies SAEAT Research and Development Namur Belgium University of Montpellier Val dAurelle Cancer Research Center, Montpellier, France. Kiel Center for Functional Genomics, University Hospital Schleswig Holstein, Kiel, Germany.

Keywords: genetics of longevity; longevity; mitochondrial DNA; mtDNA sequencing; oxidative phosphorylation.

Introduction

Research on mitochondrial biology has underlined the central role played by the mitochondrion in a number of complex traits, including aging and metabolic and degenerative diseases. Mitochondria, due to their central position between energy uptake and energy production, are involved in a number of cellular processes such as heat production, apoptosis regulation, and cellular differentiation. In addition, mitochondria are responsible for the production and regulation of the most important by-product of cellular metabolism, reactive oxygen species (ROS), which are widely considered to be one of the main causes of aging (for a review see Passarino et al., 2010; Wallace, 2010). Most of the proteins determining the biology of mitochondria Correspondence Giuseppe Passarino, Department of Cell Biology, University of Calabria, 87036, Rende, Italy. Tel.: +39 0984 492932; fax: +39But are not associated with any of the haplogroups. Here, we present the results of a very large study where over 2200 subjects older than 90 years were recruited within the framework of the Genetics of Healthy Ageing (GEHA) EU project (Skytthe et al., 2011) and coming from most of the European populations, were compared with a similar number of younger controls matched for sex and geographical origins. The frequencies of mtDNA haplogroups in 90+ and controls are summarized in Table 1 and, separately for men and women, in Table S1. We observed that in females, the haplogroups H2 and T2 are more frequent in the 90+ group than in controls (P = 0.002 and 0.02, respectively). On the other hand, among male controls, the frequency of haplogroups H1 and J2 was higher than in the 90+ group (P = 0.023 and 0.004, respectively). No association was detectable when multiple test corrections were used.