UPSC Prelims 2023 question on Aerial Metagenomics

Metagenomics (also referred to as environmental and community genomics) is the genomic analysis of microorganisms by direct extraction and cloning of DNA from an assemblage of microorganisms. It involves isolating DNA from an environmental sample, cloning the DNA into a suitable vector, transforming the clones into a host bacterium, and screening the resulting transformants.

Such an approach helps in sampling an entire habitat at one go. Researchers have shown that environmental DNA (e-DNA) can potentially identify and monitor terrestrial animals. Animals shed DNA through their breath, saliva, fur or faeces into the environment. These samples are called e-DNA.

'Aerial metagenomics' therefore refers to collecting DNA samples from air in a habitat at one go — sampling an entire airborne habitat's environmental DNA simultaneously.

Hence option (a) is the correct answer.