Fig. 1

Distribution of the differentially methylated CpG sites and clustering analysis before and after short-term smoking cessation. a Volcano plot of differentially methylated sites: red represents methylation levels elevated after short-term smoking cessation, blue represents methylation levels that declined after short-term smoking cessation. b Distribution of the CpG sites in CpG categories. c Genome-wide distribution of the differentially CpG sites. d The CpG sites number of short-term smoking cessation(Case) compared with before short-term smoking cessation (Control). e Graph-clustering was used to display these differentially methylated CpG sites and clustering analysis of their methylation values. Samples are accommodated in columns and DMCpGs in rows in the matrix. Colorbar denotes a comparison table of number and color (relatively high in red and relatively low in blue), the top sample tree represents a similar degree clustering relationship between samples, and samples of the same color indicate the same group. C1-C8: Control. N1-N8: Case. The darker the color, the greater the MCC value