Gaseous air pollutants and DNA methylation in a methylome-wide association study of an ethnically and environmentally diverse population of U.S. adults.

Abstract

Epigenetic mechanisms may underlie air pollution-health outcome associations. We estimated gaseous air pollutant-DNA methylation (DNAm) associations using twelve subpopulations within Women's Health Initiative (WHI) and Atherosclerosis Risk in Communities (ARIC) cohorts (n = 8397; mean age 61.3 years; 83% female; 46% African-American, 46% European-American, 8% Hispanic/Latino). We used geocoded participant address-specific mean ambient carbon monoxide (CO), nitrogen oxides (NO2; NOx), ozone (O3), and sulfur dioxide (SO2) concentrations estimated over the 2-, 7-, 28-, and 365-day periods before collection of blood samples used to generate Illumina 450 k array leukocyte DNAm measurements. We estimated methylome-wide, subpopulation- and race/ethnicity-stratified pollutant-DNAm associations in multi-level, linear mixed-effects models adjusted for sociodemographic, behavioral, meteorological, and technical covariates. We combined stratum-specific estimates in inverse variance-weighted meta-analyses and characterized significant associations (false discovery rate; FDR<0.05) at Cytosine-phosphate-Guanine (CpG) sites without among-strata heterogeneity (PCochran's Q > 0.05). We attempted replication in the Cooperative Health Research in Region of Augsburg (KORA) study and Normative Aging Study (NAS). We observed a -0.3 (95% CI: -0.4, -0.2) unit decrease in percent DNAm per interquartile range (IQR, 7.3 ppb) increase in 28-day mean NO2 concentration at cg01885635 (chromosome 3; regulatory region 290 bp upstream from ZNF621; FDR = 0.03). At intragenic sites cg21849932 (chromosome 20; LIME1; intron 3) and cg05353869 (chromosome 11; KLHL35; exon 2), we observed a -0.3 (95% CI: -0.4, -0.2) unit decrease (FDR = 0.04) and a 1.2 (95% CI: 0.7, 1.7) unit increase (FDR = 0.04), respectively, in percent DNAm per IQR (17.6 ppb) increase in 7-day mean ozone concentration. Results were not fully replicated in KORA and NAS. We identified three CpG sites potentially susceptible to gaseous air pollution-induced DNAm changes near genes relevant for cardiovascular and lung disease. Further harmonized investigations with a range of gaseous pollutants and averaging durations are needed to determine the effect of gaseous air pollutants on DNA methylation and ultimately gene expression.

• Authors: Katelyn M Holliday, Rahul Gondalia, Antoine Baldassari, Anne E Justice, James D Stewart, Duanping Liao, Jeff D Yanosky, Kristina M Jordahl, Parveen Bhatti, Themistocles L Assimes, James S Pankow, Weihua Guan, Myriam Fornage, Jan Bressler, Kari E North, Karen N Conneely, Yun Li, Lifang Hou, Pantel S Vokonas, Cavin K Ward-Caviness, Rory Wilson, Kathrin Wolf, Melanie Waldenberger, Josef Cyrys, Annette Peters, H Marike Boezen, Judith M Vonk, Sergi Sayols-Baixeras, Mikyeong Lee, Andrea A Baccarelli, Eric A Whitsel
• Journal: Environmental research (Environ Res) Vol. 212 Issue Pt C Pg. 113360 (09 2022) ISSN: 1096-0953 [Electronic] Netherlands
• PMID: 35500859 (Publication Type: Journal Article, Research Support, Non-U.S. Gov't, Research Support, N.I.H., Extramural)
• Copyright: Copyright © 2022 Elsevier Inc. All rights reserved.

Chemical References

• Air Pollutants
• Particulate Matter
• Ozone
• Nitrogen Dioxide

Topics

• Adult
• Air Pollutants (analysis, toxicity)
• Air Pollution (analysis)
• DNA Methylation
• Epigenome
• Female
• Humans
• Male
• Middle Aged
• Nitrogen Dioxide (analysis)
• Ozone (analysis, toxicity)
• Particulate Matter (analysis)