Meta-analysis identifies 3,207 novel DNA methylation sites linked to smoking

This meta-analysis examined DNA methylation patterns associated with smoking exposure in 45,460 participants from the Million Veteran Program, including 27,455 Europeans, 11,798 African Americans, and 4,859 Admixed Americans. The study compared ever smokers to never smokers and identified 3,207 novel probe-smoking associations, adding to the known epigenetic effects of tobacco exposure.

The analysis leveraged a large, ancestrally diverse sample to uncover methylation sites not previously reported. However, effect sizes, confidence intervals, and p-values were not reported, limiting the ability to assess the strength of these associations. The study did not report follow-up duration or adjust for potential confounders beyond smoking status.

As a meta-analysis of observational data, these findings cannot establish causality. The authors did not discuss limitations or practice implications. The results highlight the need for further validation in independent cohorts and exploration of functional relevance.

Clinically, these epigenetic markers may eventually serve as biomarkers of smoking exposure or risk, but current evidence is preliminary. No specific interventions or clinical recommendations can be drawn from this study alone.