Fig. 1

Genomic structure of the MGMT promoter. The CpG island covers the major part of the promoter region including Exon 1. The two CpG sites analyzed by the Illumina 450 K array (highlighted in red) are not associated with the DHMR as the common target region in the routinely performed assays using MS-PCR and Pyrosequencing. Our newly designed pyrosequencing assay (purple box) targets the distal section of the promoter overlapping DHMR and includes 4/6 CpG sites that highly correlate with MGMT mRNA expression