Smoking is the leading cause of accelerated aging and death worldwide. Therefore, identifying and intervening at smoke-responsive DNA methylation markers may be a primary way to reduce mortality risk Show more
Smoking is the leading cause of accelerated aging and death worldwide. Therefore, identifying and intervening at smoke-responsive DNA methylation markers may be a primary way to reduce mortality risk in the population. Many studies have investigated the association between smoking and DNA methylation in blood samples. Only a few studies have examined saliva and buccal cells in this regard. Here, we determined DNA methylation profiles in buccal cells from a total of 280 individuals. Epigenome-wide association analysis (N = 200) uncovered 61 CpG markers, including novel ones, that were significantly associated with smoke exposure in this tissue type. Functional analysis showed that they were overrepresented in the Wnt signaling pathway and fatty acid metabolism. We confirmed that AHRR, a known smoking marker in blood, is also a top locus in buccal cells. However, cg06036945 (p = 1.76 × 10 Show less