Binary relation of methylation and expression for pd-DMR genes. Each circle in the scatterplot represents 1 case of the total of 115 samples with methylation and expression data. X-axis data represent methylation β values (ranging from 0 to 1.0, equivalent to 0% to 100% methylation), y-axis data represent normalized, log2 Affymetrix HG U133plus2.0 gene expression data. The area shaded in gray in each plot represents cases with high methylation values as defined per the k-means clustering algorithm. Note that cases with a low methylation status (below the individual p-DMR cutoff; white background) can be, but are not constitutionally, highly expressed (transcriptionally permissive). In contrast, cases with high methylation status (above the cutoff; gray background) are silenced (transcriptionally locked).