Icy research reveals primitive viruses in Tibetan glacier


Scientists recently revealed the existence of 28 never-before-seen virus groups at two ice cores from a Tibetan glacier. For the past 15,000 years, this glacier on the northwestern Tibetan Plateau of China played hosts to unusual guests: an ensemble of frozen viruses, many of them unknown to modern science. The findings have been posted in a paper of the bioRxiv database, an open-access preprint repository for the biological sciences.

Crux of the Matter
  • In 2015, when researchers embarked on an expedition to retrieve the oldest ice on the planet, they were doing it to look for clues about past climate and stumbled upon the Guliya ice cap in China’s Tibet.
  • The scientists retrieved the ancient viruses by drilling 50 meters deep into the glacier ice. To rule out any contamination, they developed an original method to study the microbes in the lab.
  • Out of the 33 groups of virus genuses or genera, 28 were previously undisclosed to science. The researchers reportedly wrote in the study how the microbes differed significantly across the two ice cores.
  • The critters they found represent the microbes that were present in the atmosphere at the time they were trapped in the ice, giving scientists a window to understanding the past climate and microbial evolution.
  • Chantal Abergel, a researcher in environmental virology at the French National Centre for Scientific Research said “We are very far from sampling the entire diversity of viruses on Earth.” As human-made climate change melts glaciers the world over, these viral archives could be lost.

Virus is a small infectious agent that replicates only inside the living cells of an organism. Viruses can infect all types of life forms, from animals and plants to microorganisms, including bacteria and archaea. Since Dmitri Ivanovsky’s 1892 article describing a non-bacterial pathogen infecting tobacco plants, and the discovery of the tobacco mosaic virus by Martinus Beijerinck in 1898 about 5,000 virus species have been described in detail, although there are millions of types. Viruses are found in almost every ecosystem on Earth and are the most numerous type of biological entity. The study of viruses is known as virology, a sub-speciality of microbiology. The shapes of these virus particles range from simple helical and icosahedral forms for some species to more complex structures for others. More Info