Cell-free DNA (cfDNA) is increasingly being used by researchers throughout the world to better understand human diseases, improve diagnosis, monitoring, and prognosis.
What exactly is cell-free DNA?
CfDNA refers to tiny nucleic acid fragments that are released from cells and found in bodily fluids.
It was originally discovered in the blood of pregnant women in the late 1940s.
Cells can create and release cfDNA in a variety of scenarios, including cell death and other physiological processes.
The release of cfDNA has been linked to a variety of disease processes, including autoimmune disorders such as systemic lupus erythematosus.
How is it different from normal DNA?
Cell-free DNA
Normal DNA
Found in the bloodstream and other bodily fluids
Found within the cell nucleus or mitochondria
Released from dying or dead cells into the circulation
Remains within the cell’s nucleus or mitochondria
Exists in a fragmented form
Exists as an intact double-stranded helix
Can be isolated and analyzed from blood samples
Requires cell extraction and purification for analysis
Provides valuable genetic information for personalized medicine
Forms the basis of genetic inheritance and traits
Valuable in infectious disease diagnosis and monitoring
Not used for infectious disease diagnosis
Used in forensics for DNA profiling and crime investigations
Not typically used in forensics
Applications of CfDNA
Non-Invasive Prenatal Testing (NIPT)
Identify genetic anomalies in foetuses Down syndrome, Edwards syndrome, and Patau syndrome screening
Cancer Screening and Monitoring
Recognise genetic alterations in tumour cells Determine the type of cancer Keep track of how the treatment is working and how the condition is progressing.
Transplant Rejection Monitoring
Assess the immunological response following organ transplantation. Organ rejection can be detected early.
Infectious Disease Diagnosis
Determine the presence of viruses and bacteria in the bloodstream. Aid in the diagnosis of illnesses and the direction of treatment
Personalized Medicine
Provide genetic information to enable personalised treatment plans. Allow for precise medicine based on an individual’s genetic profile.
Tracking Tumour Mutations
Drug-resistant mutations in cancer patients should be monitored for therapy changes.
Recent Therapeutic Advances GEMINI Test:
Johns Hopkins Kimmel Cancer Centre researchers created a novel test called ‘GEMINI’ that employs cfDNA for early cancer detection. They obtained over 90% accuracy in diagnosing lung cancer, even in early-stage instances, by analysing genetic changes and applying machine learning.
Potential Impact: Using cfDNA to diagnose cancer early could greatly improve patient outcomes and survival rates.
