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Daily News Analysis


5th February, 2024 Health


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Picture Courtesy: https://www.livescience.com/health/viruses-infections-disease/mysterious-virus-like-obelisks-found-in-the-human-gut-and-mouth

Context: The identification of "Obelisks," a novel class of virus-like entities in the human gut and mouth, raises intriguing questions about their potential impact on the human microbiome.

Key Highlights of the research

  • Discovery of Viroids in Human Gut and Mouth: Scientists have identified a new class of virus-like entities called "Obelisks" in the human gut and mouth. These viroids may influence gene activity within the human microbiome.
  • Viroid Characteristics: Viroids are tiny loops of RNA, a genetic cousin of DNA, lacking protective shells and without instructions to build proteins. Originally thought to infect only plants, recent studies suggest viroids may infect animals, fungi, or bacteria.
  • Host Confirmation: Streptococcus sanguinis, a common bacterium in the mouth, is identified as one host for Obelisks. Other potential hosts, likely bacteria, are yet to be confirmed.
  • Viroid Complexity: Some Obelisks contain instructions for enzymes needed for replication, indicating greater complexity compared to previously described viroids.
  • Presence in Metatranscriptomes: Obelisks were found in 7% of human fecal metatranscriptomes, providing insight into gene activity in the gut microbiome. In mouth metatranscriptomes, Obelisks were present in about 53% of the samples.
  • Impact on Human Health: It is still unknown how or whether these viroids affect human health. There is speculation that viroids may shape the human microbiome, especially considering their ability to infect bacteria.
  • Evolutionary Debate: Ongoing discussion surrounds whether viruses evolved from viroids or if viroids evolved from viruses. The discovery of Obelisks may contribute to this debate.


  • The discovery of Obelisks adds a new dimension to our understanding of the virome within the human body and prompts further investigation into their potential roles and impacts on human health.


Q. What are Obelisks, as recently discovered by scientists?

A) A new species of deep-sea fish.

B) A type of bacteria found in the human gut.

C) A novel class of virus-like entities in the human gut and mouth.

D) A new medication being tested for treating gut diseases.

Answer: C