Next, we developed a heatmap to represent the methylation changes that are occurring at the promoter and intergenic regions as correlated to expression changes (Fig. 4I). We observe that these methylation changes are concentrated around the promoter and transcriptional start site (Fig. 4J) and are inversely correlated to expression changes (Fig. 4K). However, there are several changes in methylation that are not necessarily correlated to changes in gene expression, suggesting interplay between transcript changes and changes in DNA methylation status beyond the simple inverse correlation between epigenetics and transcription. This may be due in part to the fact that genes involved in methyltransferase activity are changing as observed from our ontological analysis in Figure 1F. Thus, EtOH treatment does not only change the transcriptional profile but also the epigenetic profile, which may have more profound implications if these epigenetic changes are permanent and transmissible.
