Table 2.

Some current methods to diagnose cancer based on cell-free DNA analysis.

Molecular analysis of ctDNA/cfDNAGenetic alterationsSequencing depthControlReference
Targeted sequencing of 507 genes previously associated with cancerSingle-nucleotide variants, insertions, and deletions60,000WBC DNA analysis(38)
Whole-genome sequencingCopy-number variations30WBC DNA analysis(39, 40)
Whole-genome bisulfite sequencingMethylation differences30WBC DNA analysis(38, 42)
Genome-wide fragmentation patterns of cfDNAAltered fragmentation profiles in a position-specific manner0.5–2cfDNA from healthy individuals(14, 41)
  • Abbreviation: WBC, white blood cell.