Cell free DNA is found to be promising in the field of disease discovery.
What is cfDNA?
DNA is a molecule that carries genetic information for the development and functioning of an organism.
Cell-free DNA (cfDNA) refers to small DNA fragments found in the bloodstream and other bodily fluids, such as spinal fluid and urine.
These fragments are derived from various sources, including the breakdown of cells, the release of DNA from damaged or dying cells, and the shedding of DNA by normal cells.
The presence of cfDNA in bodily fluids is an indication of various processes that include physical injury, inflammation, and cancer.
What are the applications of cfDNA?
Non-invasive prenatal test (NIPT) - NIPT is a screening test that can be performed during pregnancy to assess the risk of chromosomal abnormalities in the fetus, such as
Down syndrome (trisomy 21)
Edwards syndrome (trisomy 18)
Patau syndrome (trisomy 13)
Cancer treatment-The presence of cfDNA with specific genetic abnormalities can indicate the presence of cancer.
The analysis of cfDNA can be used to diagnose cancer, monitor the treatment effectiveness, and detect recurrence after treatment.
GEMINI- Genome-wide Mutational Incidence for Non-Invasive detection of cancer adopts a whole-genome-sequencing approach to cfDNA extracted from patients.
Biomarker- CfDNA finds its application in the 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.
Heart attack- The analysis of cfDNA has been studied as a potential tool for the diagnosis and prognosis of acute myocardial infarction (heart attack).
Stroke- The presence of cfDNA in the blood is an indicator of brain injury in stroke patients, and the analysis of cfDNA has been studied as a potential tool for the diagnosis and prognosis of stroke.
Autoimmune diseases- The analysis of cfDNA is a potential tool for diagnosing and monitoring autoimmune diseases, such as rheumatoid arthritis and systemic lupus erythematosus.
Pregnancy complications- The analysis of cfDNA is a potential tool for diagnosing and monitoring complications during pregnancy, such as preterm labor and preeclampsia.
Organ transplantation- It helps in understanding why a body is rejecting a transplanted organ.
DNA obtained from the donor who is donating the organ – called donor-derived cfDNA, dd-cfDNA – could provide an early yet accurate estimate of how well the organ is being taken up.
Circulating tumor DNA (ctDNA)
ctDNA refers to a small subset of the cfDNA and consists of small DNA fragments released into the bloodstream by cancer cells.
ctDNA can be detected in the blood of individuals with cancer and can provide information about the characteristics of the cancer.
Size- ctDNA fragments are typically smaller than normal DNA fragments due to the presence of breaks and mutations in the DNA.
Composition- ctDNA comprises both normal DNA and DNA with mutations or abnormalities.
Stability- ctDNA is relatively stable in the bloodstream and can be detected for an extended period after it is released from the cancer cells.
Concentration- The concentration of ctDNA in the bloodstream can vary depending on the stage and size of the cancer.
Heterogeneity- ctDNA can be highly heterogeneous, meaning it can contain various mutations and abnormalities making it challenging to detect and analyze accurately.
