Fig. 2From: X chromosome-wide analysis identifies DNA methylation sites influenced by cigarette smokingSmoking-related DNA methylation levels of a cg07764473 (BCOR) and b cg21380860 (TSC22D3) among never (light gray), past (medium gray), and current smokers (dark gray) in male twins. Each black line indicates an individual’s DNA methylation level measured by β-value. Red line indicates the mean level of β-values of each group of smokersBack to article page