Figure 1: The differentially hypomethylated and hypermethylated CpG profiles associated with low level benzene exposure and functional analysis. (a) Hierarchical cluster of 2159 differentially methylated CpG sites in low level benzene exposure workers compared with health controls. Among them, there are 1546 differential hypermethylated and 613 hypomethylated CpG sites. The heatmap color corresponds to the Beta-value of the measured CpG-sites. The Beta-value is in the range of 0 (shown in green) and 1 (shown in red) with 0 representing purely unmethylated and 1 representing purely methylated. Each row represents a separate sample and each column represents a CpG site. (b) GO analysis of differential hypermethylated genes in low level benzene exposure workers compared to health controls. (c) GO analysis of differential hypomethylated genes in low level benzene exposure workers compared to health controls. X axis, negative logarithm of the P value (-LgP), the larger the value was, the smaller the P value was. Y axis, the name of the gene ontology category, significant GO terms of differential methylated genes.