Cancer detection and tissue of origin determination with novel annotation and scoring of cell-free methylated DNA

In a recent paper, Guo et al . (1) analysed the methylation of DNA fragments circulating in the blood plasma that are released when cells die. Their analysis used a novel approach to annotate DNA methylation and a methylation status score, which captures both average methylation level and the pattern of co-methylation. They were able to detect lung and colorectal cancers and to predict their tissue of origin.