Figure 3.

Quantile-quantile plots demonstrating degree of differential methylation in 5003 single gene vs. 657 C/C (A) and 97 C/N (B) bidirectional promoters restricted to CpG islands. For C/C bidirectional promoters, at every quantile of rank differential methylation, the rank of differential methylation for single gene promoters was always lower (i.e., greater differential methylation). For C/C bidirectional promoters, all results were statistically significant. For C/N bidirectional promoters, this trend mostly continued, but it was much weaker and was not apparent for all cancers.