Assay performance tested on samples from patients with colorectal cancer. Electropherograms after separation of methylation-restricted single nucleotide primer extension (MR-SNuPE) products obtained from plasma taken from patients with colonoscopy-verified colorectal cancer. Plasma from (a-c) patient with cancer, obtained from Proteogenex (PRO6, PRO20) or Oncomatrix (OMA19); (d) healthy individual, obtained from Oncomatrix (OMA8). (e) Normal blood plasma (5 ml) spiked with 12.5 ng methylated DNA (Chem). Peaks were assessed by the relative signal retention times as described in the legend to Figure 2. UP = unextended primer, M = methylated signal; NTC = SNuPE reaction with water.