As the earth warms, ice melts, and it occasionally gives up things we’d rather it didn’t. A study of ice from a nearly 15,000-year-old Tibetan glacier suggests that it may contain a variety of viruses that have never been seen before. The viruses discovered thus far are unlikely to infect people, let alone endanger our health, but we don’t know what else is out there.
“These glaciers grew gradually, and along with dust and gases, many, many viruses were also deposited in that ice,” Ohio State University’s Dr Zhi-Ping Zhong said in a release. “The glaciers in western China have received little attention, and our objective is to utilize this data to reconstruct historical habitats. Viruses are present in these habitats.”
Zhong and co-authors contributed to this by examining ice cores obtained at the Guliya peak, which is 6,700 meters (22,000 ft) above sea level. The authors claim to have discovered the genetic codes for 33 viruses, just four of which were previously unknown. These four are phages, which are viruses that infect bacteria and are more likely to be used by humans than to represent a threat.
We know less about the other 29 viral kinds, but they are considered to exist (if a virus can be called to be alive) in soil bacteria or plants, rather than mammals. Many of their presumed hosts, especially Methylobacterium, were also discovered frozen in the ice.
“These are viruses that would have flourished in harsh conditions,” co-author Professor Matthew Sullivan explained. “These viruses have gene signatures that allow them to infect cells in cold settings – absolutely bizarre genetic markers for how a virus may live in harsh temperatures. These are difficult signatures to extract, and the method developed by Zhi-Ping to decontaminate the cores and study microbes and viruses in ice could aid in the search for these genetic sequences in other extreme icy environments, such as Mars, the moon, or closer to home in Earth’s Atacama Desert.”
Finding viruses on the Moon would be a scientific shock, to say the least, but astrobiologists would want to extend similar techniques to some of the Solar System’s outermost moons.
Microbes were discovered in glacial ice more than a century ago, according to the report. However, the problem has received a lot more attention recently as scientists have grown accustomed to the thought of a world where glacier melt is accelerating. Viruses have only been found in glacial ice twice previously, although this might be due to a lack of searching or the fact that most ice cores originate from Antarctica and Greenland, which are distant from potential origins.
Viruses, especially recently, have been thought to inflict nothing but harm to their hosts. However, some are genuinely advantageous, and Zhong and Sullivan believe such was the case for the majority of those discovered. These viruses may help bacteria survive in the harsh surroundings around the glacier by transmitting genes that aid in nutrient acquisition.