Epigenome-wide association study of nuclear DNA methylation in relation to mitochondrial heteroplasmy.

Meng Lai, Kyeezu Kim, Yinan Zheng, Christina A Castellani, Scott M Ratliff, Mengyao Wang, Xue Liu, Jeffrey Haessler, Tianxiao Huan, Kwadwo Bonsu, Charles Newcomb, Kyler McKessy, Lawrence F Bielak, Wei Zhao, Roby Joehanes, Jiantao Ma, Xiuqing Guo, JoAnn E Manson, Megan L Grove, Jan Bressler, Kent D Taylor, Tuuli Lappalainen, Silva Kasela, Thomas W Blackwell, Nicole J Lake, Jessica D Faul, Kendra R Ferrier, Stephen C Ekker, Lifang Hou, Charles Kooperberg, Alexander P Reiner, Kai Zhang, Patricia A Peyser, Myriam Fornage, Eric Boerwinkle, Laura M Raffield, April P Carson, Stephen S Rich, Yongmei Liu, Daniel Levy, Jerome I Rotter, Jennifer A Smith, Dan E Arking, Chunyu Liu,, Nature communications 16, 10962 (2025)
DOI
10.1038/s41467-025-65845-2
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Abstract

We analyze 10,986 participants (mean age 77; 63% women; 54% non-White) across seven U.S. cohorts to study the relationship between mitochondrial DNA (mtDNA) heteroplasmy and nuclear DNA methylation. We identify 597 CpGs associated with heteroplasmy burden, generally showing lower methylation. These CpGs are enriched in dynamically regulated island shores and depleted in CpG islands, indicating involvement in context-specific rather than constitutive gene regulation. In HEK293T cells, we introduce a truncating mtDNA mutation (MT-COX3, mt.9979) and observe a positive correlation between variant allele fraction and methylation at cg04569152, supporting a direct mtDNA-nDNA epigenetic link. Many heteroplasmy-associated CpGs overlap with known methylation-trait associations for metabolic and behavioral traits. Composite CpG scores predict all-cause mortality and incident CVD, with one-unit increases associated with 1.27-fold and 1.12-fold higher hazards, respectively. These findings suggest an mtDNA-nDNA epigenetic connection in aging and disease, though its direction and mechanisms remain to be studied.