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United Kingdom and United States

Scientists first reported evidence of microbes in the accretion ice in 1999. Since then, a different team led by Scott O. Rogers has been identifying a variety of bacteria and fungi from accretion ice (not from the subglacial water layer) collected during U.S. drilling projects in the 1990s. According to him, this indicates that the lake below the ice is not sterile but contains a unique ecosystem. Then Scott Rogers published in July 2013 that his team performed nucleic acid (DNA and RNA) sequencing and the results allowed deduction of the metabolic pathways represented in the accretion ice and, by extension, in the lake. The team found 3,507 unique gene sequences, and approximately 94% of the sequences were from bacteria and 6% were from Eukarya. Taxonomic classifications (to genus and/or species) or identification were possible for 1,623 of the sequences. In general, the taxa were similar to organisms previously described from lakes, brackish water, marine environments, soil, glaciers, ice, lake sediments, deep-sea sediments, deep-sea thermal vents, animals and plants. Sequences from aerobic, anaerobic, psychrophilic, thermophilic, halophilic, alkaliphilic, acidophilic, desiccation-resistant, autotrophic, and heterotrophic organisms were present, including a number from multicellular eukaryotes.

In 2020, Colby Gura and Scott Rogers extended their study of Lake Vostok accretion ice, as well as the basal ice flowing into the lake. They found that the basal ice contained an almost completely different community of organisms compared to those found in the lake accretion ice, indicating that they signified two completely different ecosystems. Additional bacteria and eukaryotes were reported. The highest diversity of organisms in the lake ice was significantly associated (p<0.05) with higher concentrations of ions and amino acids. While their previous work indicated the presence of bacteria that inhabit fish intestines, no sequences from fish were found. However, in the 2020 study, they found an rRNA sequence that was >97% similar to that from a rock cod common along the coast of Antarctica (Notothenia coriiceps). This is the first report of a fish species possibly residing in Lake Vostok. The fish is known to produce antifreeze proteins.

Microbiologist David Pearce of the University of Northumbria in Newcastle, UK, stated that the DNA could simply be contamination from the drilling process, and not representative of Lake Vostok itself. The old ice cores were drilled in the 1990s to look for evidence of past climates buried in the ice, rather than for life, so the drilling equipment was not sterilized. Also Sergey Bulat, a Lake Vostok expert at the Petersburg Nuclear Physics Institute in Gatchina, Russia, doubts that any of the cells or DNA fragments in the samples would belong to organisms that might actually exist in the lake. He says that it is very probable that the samples are heavily contaminated with tissue and microbes from the outside world.

The contamination possibility has been refuted by Scott Rogers, because the control measures were rigorous, and the combinations of organisms found in each of the ice samples were consistent with organisms living in a cold lake and ice (including a sequence from an Antarctic rock cod), and were inconsistent with contamination introduced while sampling or from the lab procedures. Also, all of the lab procedures were performed in parallel with ice samples from Lake Erie, and the two resulting data sets were completely different. The Lake Erie sample exhibited many signals of human habitation, while the Lake Vostok ice samples exhibited no signals of human habitation. The Lake Erie sample also had an almost completely different profile of bacterial and eukaryotic phyla.