TP53 mutations in patient #5: Left panels illustrate read alignments using Integrative Genomics Viewer. Right panels show the percentage of alternative reads found in each compartment [i.e., tissue (top), PBMC (middle), plasma (bottom)]. Two adjacent mutations of TP53, located 3 base pairs apart, with a variant allele fraction of 80% were detected in tissue. The corresponding alternative alleles of these 2 mutations were not detected in PBMC, thus excluding germline events. Ultra-deep sequencing of plasma DNA detected the same 2 mutations in approximately 4% of circulating DNA fragments. Mutations in plasma are found in the exact same reads, identifying their shared origin from their tissue counterparts.