Cell-free DNA
2023 AUG 5
Preliminary >
Science and Technology > Biotechnology > Basics of biotechnology
Why in news?
- Researchers worldwide are increasingly using Cell-free DNA (cfDNA) as a valuable tool to better comprehend human diseases, improve diagnosis, monitoring, and prognosis.
What is Cell-free DNA?
- CfDNA refers to small fragments of nucleic acids that are released from cells and found outside the cell in body fluids.
- Its discovery dates back to the late 1940s when it was first observed in the blood of pregnant women.
- cfDNA can be generated and released from cells in various situations, such as cell death and other physiological processes.
- The release of cfDNA is associated with several disease processes, including autoimmune diseases like systemic lupus erythematosus.
How is it different from normal DNA?
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Cell-free DNA
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Normal DNA
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Found in the bloodstream and other bodily fluids
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Found within the cell nucleus or mitochondria
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Released from dying or dead cells into the circulation
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Remains within the cell’s nucleus or mitochondria
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Exists in a fragmented form
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Exists as an intact double-stranded helix
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Can be isolated and analyzed from blood samples
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Requires cell extraction and purification for analysis
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Provides valuable genetic information for personalized medicine
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Forms the basis of genetic inheritance and traits
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Valuable in infectious disease diagnosis and monitoring
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Not used for infectious disease diagnosis
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Used in forensics for DNA profiling and crime investigations
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Not typically used in forensics
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Applications of Cell-free DNA:
- Non-Invasive Prenatal Testing (NIPT):
- Cell-free DNA serves as a valuable tool for screening chromosomal abnormalities in developing foetuses, such as Down syndrome.
- NIPT replaces invasive procedures such as amniocentesis, minimizing risks for both expectant mothers and foetuses.
- Analysis of cfDNA in maternal blood provides crucial information about the foetus's genetic health.
- Early Cancer Detection:
- Identifying cancers at their initial stages for prompt treatment.
- The 'GEMINI' test utilizes cfDNA sequencing to detect lung cancer with high accuracy.
- Combining cfDNA analysis with existing methods enhances overall cancer detection.
- Monitoring Organ Transplants:
- Donor-derived cfDNA offers a promising approach to monitor the health and acceptance of transplanted organs.
- Fluctuations in cfDNA levels can indicate organ rejection or acceptance before other markers become evident.
- Early detection of rejection allows for timely intervention and improved outcomes in organ transplantation.
- Neurological Disorder Biomarkers:
- Investigating cfDNA's potential as a biomarker for neurological disorders.
- Aiding in the diagnosis and monitoring of conditions like Alzheimer's disease, neuronal tumours, and stroke.
- Metabolic Disorder Insights:
- Exploring cfDNA's role as a biomarker for metabolic disorders.
- Detection and management of conditions such as type-2 diabetes and non-alcoholic fatty liver disease.
- Advancing Disease Research:
- Researchers use cfDNA analysis to study disease mechanisms, monitor treatment effectiveness, and gain insights into disease pathways.
PRACTICE QUESTION
UPSC 2019
With reference to the recent developments in science, which one of the following statements is not correct?
(a) Functional chromosomes can be created by joining segments of DNA taken from cells of different species.
(b) Pieces of artificial functional DNA can be created in laboratories.
(c) A piece of DNA taken out from an animal cell can be made to replicate outside a living cell in a laboratory.
(d) Cells taken out from plasma and animals can be made to undergo cell division in laboratory petri dishes.
Answer
