Some fragments of DNA are ‘released’ from their containers and are present outside the cell, in body fluids. These small fragments of nucleic acids are widely known as cell-free DNA (cfDNA).
- cfDNA can be generated and released from a cell in a number of possible situations, including when a cell is dying and the nucleic acids become degraded.
- Since an array of processes modulates the degradation, the amount, size, and source of the cfDNA can vary across a range as well.
- In addition, the release of cfDNA could occur together with a variety of processes, including those required for normal development, those related to the development of certain cancers, and those associated with several other diseases.
- One of the initial reports of the levels of cfDNA in diseases came from studies that were taking a closer look at an autoimmune disease: systemic lupus erythematosus – where the body’s own immune system attacks specific cells.
- Researchers around the world are increasingly finding cfDNA to be a useful tool to understand human diseases and to use the knowledge to improve diagnosis, monitoring, and prognosis.
- One of the most widely used applications of cfDNA has been in screening foetuses for specific chromosomal abnormalities, an application known as non-invasive prenatal testing.
- The availability of affordable genome-sequencing approaches will allow clinicians to sequence cfDNA fragments that correspond to foetal DNA.
- The cfDNA-based approach has now become the mainstay for screening high-risk pregnancies.
- Another emerging application of cfDNA is in the early detection, diagnosis, and treatment of cancers.
- There are a number of emerging applications of cfDNA, including in understanding why a body is rejecting a transplanted organ.
- There have already been some reports suggesting that cfDNA could be used as a biomarker for neurological disorders like Alzheimer’s disease, neuronal tumours, stroke, traumatic brain injury, and even metabolic disorders like type-2 diabetes and non-alcoholic fatty liver disease.
