Cell-free DNA (cfDNA) (cfDNA)

Cell-free DNA (cfDNA) consists of extracellular DNA fragments released into the bloodstream and other body fluids through processes such as apoptosis, necrosis, or active secretion (Source: NIH/NCBI). The specific mention of 202 SNP loci refers to a methodology used in advanced liquid biopsy assays, most notably the Prospera test by Natera, which utilizes a massively multiplexed PCR (mmPCR) approach to target 202 single nucleotide polymorphisms (SNPs) to differentiate donor-derived cfDNA (dd-cfDNA) from recipient DNA (Source: Sigdel et al., 2018, J. Clin. Med.). This quantification serves as a sensitive, non-invasive biomarker for organ transplant rejection, as increased levels of dd-cfDNA correlate with graft injury and active rejection (Source: Natera). In oncology, cfDNA is utilized to detect somatic mutations and monitor minimal residual disease, providing a real-time snapshot of tumor dynamics (Source: Heitzer et al., 2015, Clinical Chemistry). Because cfDNA is a byproduct of cellular turnover rather than a functional protein or receptor involved in a disease-driving signaling pathway, it is not considered a therapeutic target for drug development. Instead, it is a critical diagnostic analyte used to guide the management of immunosuppressive therapies and evaluate treatment efficacy.

Other names

cfDNACirculating cell-free DNADonor-derived cell-free DNAdd-cfDNACirculating tumor DNActDNALiquid biopsy analyte

Not applicable as cell-free DNA is a diagnostic biomarker and not a therapeutic target for pharmacological intervention.