Figure 2.

(A) Volcano plots of the differentially methylated positions with x and y axes displaying, respectively, the delta beta values (effect size) and the log10 of the P values for each CpGs site. Hypermethylated and hypomethylated CpGs in LBP vs controls (delta beta > 10% and P < 0.05) are represented in red and blue, respectively. (B) Heatmap representation of the methylation profile of the selected CpGs in both women and men used to construct the (C) polygenic methylation score. Two-way analysis of variance (ANOVA) followed by Sidak multiple comparisons, ** = P < 0.01, *** = P < 0.001, **** = P < 0.0001. *LBP, low back pain; Not DM = not differentially methylated, NS, no significant; W, women; M, men.