Global DNA Methylation is influenced by smoking behavior

Background: The level of epigenetic DNA methylation is an important factor in the pathogenesis of various human diseases. Methods: As smoking may influence DNA methylation, we investigated the effect of smoking habits on global DNA methylation in 313 genomic DNA samples. Results: We did not find an effect of smoking on global DNA methylation. However, there was an association of the offspring's DNA methylation with paternal DNA methylation that was strongest if both had never smoked ((R2corr=0.408, Beta=0.683, P=0.020) and completely vanished if the offspring smoked or had ever smoked. Conclusion: These findings suggest that smoking influences global DNA methylation.