Linkage between mitochondrial genome alterations, telomere length and aging population

Abstract

We studied telomere length (TL) and mitochondrial DNA (mtDNA) copy number variations in individuals from Latvian Caucasian population in different age groups. We showed a positive correlation between TL and mtDNA copy number in individuals of up to 90 years of age; however, this correlation was not observed in the 90–100 years age group. While TL shortened with age and mtDNA content decreased with increasing age, in this study it was observed that mtDNA copy number in nonagenarians was slightly higher than in the 60–89 years age group. The presence of heteroplasmy in the mtDNA HVS-I control region did not correlate with TL and mtDNA copy number. TL and mtDNA values also did not differ between mitochondrial haplogroups. In conclusion, while both TL and mtDNA are involved in the aging process and link between these cell components exists, nonagenarians may have differences in senescence-related pathways and systems, which may function as a protective mechanism that allows them to live longer.

Keywords:

• Mitochondria
• nonagenarians
• telomeres
• mtDNA copy number
• heteroplasmy
• haplogroups

Acknowledgments

We acknowledge Astrida Krumina, Linda Piekuse (Riga Stradins University) and also administrators of the Genome Database of the Latvian Population for providing DNA samples used in this study, and Latvian Biomedical Research and Study Centre.

Disclosure statement

The authors report no conflicts of interest. The authors alone are responsible for the content and writing of the paper.

Additional information

Funding

This work was supported by grants from the European Social Fund no.2013/0039/1DP/1.1.1.2.0/13/APIA/VIAA/038.