cell-free DNA

Syllable breakdown

Dictionary meaning

fragments of DNA circulating in blood plasma that have been released from dying cells throughout the body, without being contained within intact cells; cell-free DNA (cfDNA) includes tumour-derived circulating tumour DNA (ctDNA) shed by cancer cells, fetal DNA shed into the maternal circulation during pregnancy, and DNA from transplanted organs and inflammatory tissues; liquid biopsy technologies exploit cfDNA to detect cancer at early stages, monitor treatment response, identify mutations driving drug resistance, and screen for chromosomal abnormalities in fetal development through non-invasive prenatal testing (NIPT); the ability to obtain diagnostic genetic information from a simple blood draw, without tissue biopsy, is transforming cancer diagnostics and prenatal screening