Background: Smoking is a risk factor for many human diseases. DNA methylation has been related to smoking, but genome-wide methylation data for smoking in Chinese populations is limited.
Objectives: We aimed to investigate epigenome-wide methylation in relation to smoking in a Chinese population.
Methods: We measured the methylation levels at > 485,000 CpG sites (CpGs) in DNA from leukocytes using a methylation array and conducted a genome-wide meta-analysis of DNA methylation and smoking in a total of 596 Chinese participants. We further evaluated the associations of smoking-related CpGs with internal polycyclic aromatic hydrocarbon (PAH) biomarkers and their correlations with the expression of corresponding genes.
Results: We identified 318 CpGs whose methylation levels were associated with smoking at a genome-wide significance level (false discovery rate < 0.05), among which 161 CpGs annotated to 123 genes were not associated with smoking in recent studies of Europeans and African Americans. Of these smoking-related CpGs, methylation levels at 80 CpGs showed significant correlations with the expression of corresponding genes (including RUNX3, IL6R, PTAFR, ANKRD11, CEP135 and CDH23), and methylation at 15 CpGs was significantly associated with urinary 2-hydroxynaphthalene, the most representative internal monohydroxy-PAH biomarker for smoking.
Conclusion: We identified DNA methylation markers associated with smoking in a Chinese population, including some markers that were also correlated with gene expression. Exposure to naphthalene, a byproduct of tobacco smoke, may contribute to smoking-related methylation.
1Department of Occupational and Environmental Health, and 2Ministry of Education Key Lab for Environment and Health, School of Public Health, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, China; 3Department of Epidemiology, Harvard T.H. Chan School of Public Health, Boston, Massachusetts, USA; 4Department of Cardiology, Union Hospital, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, China; 5Department of Cardiology, People’s Hospital of Zhuhai, Zhuhai, China; 6Department of Cardiology, Bao’an Hospital, Shenzhen, China; 7Department of Cardiology, Wuhan Central Hospital, Wuhan, China; 8Department of Nutrition, Harvard T.H. Chan School of Public Health, Boston, Massachusetts, USA; 9Channing Division of Network Medicine, Department of Medicine, Brigham and Women’s Hospital and Harvard Medical School, Boston, Massachusetts, USA; 10Department of Biostatistics, Harvard T.H. Chan School of Public Health, Boston, Massachusetts, USA
Recommended Citation:
Xiaoyan Zhu,1,2* Jun Li,et al. Genome-Wide Analysis of DNA Methylation and Cigarette Smoking in a Chinese Population[J]. Environmental Health Perspectives,2016-01-01,Volume 124(Issue 7):966