Expression correlations between the three genes. Heat maps showing the TPM expression of all promoters in sub-regions of brain and brain related primary cells in mouse (a) and humans (b). Expression of Mecp2 p1 appears to be in contrast with the expression of the main promoter of Foxg1 in mouse (pA) and in humans (p1). The trees above the heatmaps show clustering according to expression. Plots in panels c to f show correlation between the three genes in mouse (panels c and e) and human (panels d and f) as labeled. The expected negative correlation based on the heatmap between MECP2 and FOXG1 could not be confirmed in either species across all samples (panels c and d). We found positive correlation (23-49%) between Cdkl5 and Mecp2 in both species (panels e and f).