Figure 4. . Technical and biological validation of the 850K MethylationEPIC microarray.

Comparison of methylation values from HumanMethylation450 and their corresponding shared CpG sites present on MethylationEPIC microarray (A) for a renal tumor sample (RCC9). Assay reproducibility (B) of methylation measurements when using technical replicates on a normal colon (NC22A) sample. Correlation plot (C) of the methylation values obtained from a FFPE sample (RCC9-FFPE) when compared with its match biopsy of the same tumor that was preserved as FF (RCC9). 5-hmC value representation (D), where the same sample was treated as per conventional bifsulfite conversion or as per oxBS. Differences on oxBS with bifsulfite conversion are due to the level of 5-hydroxymethylation, where the absence of 5-hmC has been modeled as a discontinue red line. Frequency of hydroxymethylaton values (E) as a result of subtracting the oxBS values (due to 5-mC) from the BS values (due to 5-mC + 5-hmC) for each CpG site included on the 850K array.

5-hmC: 5-hydroxymethylation; FF: Fresh frozen; FFPE: Formalin-fixed paraffin-embedded; oxBS: Oxidative bisulfite conversion.