Context:
Recently, scientist estimated that the total taxonomic diversity of Chilika lagoon in Odisha is about 1,071 families across the tree of life using environmental DNA (eDNA) method.
About eDNA:
- It is the nuclear or mitochondrial DNA that is released from an organism into the environment through natural processes during their lifetime or after death.
- Sources of eDNA – Secreted feces, mucous, and gametes; shed skin and hair; and carcasses.
- eDNA method – A non-invasive method to assess the total biodiversity of any ecosystem by sequencing the DNA found in the environments.
- Developed by – Laboratory for the Conservation of Endangered Species (LaCONES), a CSIR-Centre for Cellular and Molecular Biology (CCMB) laboratory headquartered in Hyderabad.
- Sample size – Just a few litres of water, soil, or even air.
- Working mechanism – A molecular approach is applied to filter out eDNA from environmental samples, read their sequences, and thus, identify the source of the eDNA.
Polymerase chain reaction (PCR) is used to amplify DNA for sequencing while quantitative PCR (qPCR) is typically used to detect and quantify DNA.
Significance –
- It is cheaper, faster, and highly scalable to large freshwater and marine ecosystems which can help in monitoring and conserving the rich biodiversity of our country.
- It can detect all kinds of organisms, including viruses, bacteria, archaea, and eukaryotes as well.
- eDNA can also reveal the presence of human remains.
Scientists have collected samples of seawater from the vicinity of a plane wreck of the 2nd World War to look for floating eDNA.
Source: The Hindu
Previous Year Question
‘Microsatellite DNA’ is used in the case of which one of the following?
[UPSC Civil Services Exam – 2023 Prelims]
(a) Studying the evolutionary relationships among various species of fauna
(b) Stimulating ‘stem cells’ to transform into diverse functional tissues
(c) Promoting clonal propagation of horticultural plants
(d) Assessing the efficacy of drugs by conducting series of drug trials in a population
Answer: (a)