Figure 1. Gender Heatmap of X-linked CpG Loci.

DNA methylation is involved in the transcriptional activation of genes on one of the two X chromosomes in female somatic cells. In general, male and female cases clustered together with methylation levels of the majority of X-linked genes correlating well with the gender of the tissue source (i.e. little-to-no methylation in male samples and hemi-methylation in female samples). Sample gender is represented above the heatmap (pink = female, blue = male). Methylation is represented by the beta value, or percent of total signal with green representing low methylation and red representing hemi-methylation. 51 of 84 loci within X-linked genes were differentially methylated (p<0.05) between males and females.