In Tibetan ice was a virus by the age of 15 thousand years

Biologists reported the rare find: the viruses in the multi-millennial layer of ice. Moreover, the authors have developed a method that will help to look for viral particles in many other samples of ancient ice.

the Discovery is described in the Preprint scientific articles published on the website researchers from several research centers in the United States.

Viruses in samples of glacial ice – almost terra incognita for humanity. The authors of the new study found in the scientific literature only two reports about such relics. So, in 1999, researchers reported on the biochemical traces of tomato mosaic virus in the sample the Greenland ice-age-140 thousand years. Moreover, particles similar to the virus were found in the layer of Antarctic ice at a depth of 2.7 kilometers.

it is not reported on the decoding of the genomes of the detected viruses. No waste and procedures for their search in the ice cores (the cores extracted from drilled wells). This gap and undertook to complete the work.

They studied two samples taken on the Tibetan plateau in 1992 and 2015, respectively. Meanwhile, the scientists who won the cores did not comply with sterility (after all, originally the ice was not supposed to be subjected to a microbiological study). So biologists had to develop a cleaning procedure of the samples from later biological contaminants.

to test their method, they created artificial cores of sterile water. Scientists have polluted their surface bacteria and viruses.

Then the surface layer of ice was removed. Then the core was washed with ethanol, so as to melt about 0.5 inches of ice. Finally, the test sample was washed with sterile water to melt the same amount.

After that, researchers took the analysis of ice particles and found that all microbial contamination is removed. Proving thus the effectiveness of such cleaning, they applied it to the Tibetan cores.

the Researchers found in the ancient ice viruses 33 genera, five of which were not previously known to science. Together with found numerous viruses bacteria which are the ones likely parasitized. The authors believe that germs and viruses are tormenting them fell into the ice from the air.

I Wonder what part of “viral population” of ice changes with depth. According to scientists, this may reflect climatic changes that took place in Tibet in different periods.

This study may be the beginning of a systematic search for viruses in ice cores. Such research will help scientists better understand the microcosm millennia ago.

By the way, earlier “News.Science” ( wrote about radioactive substances in glaciers in different parts of the world and about the ancient air samples preserved in polar ice.

Text: To.Science