New Study: Microorganisms Still Live in Ötzi's Tissue

Four Yeast Genera in Focus

Specifically, the researchers identified the four yeast genera "Phenoliferia," "Goffeauzyma," "Mrakia," and "Glaciozyma." These cold-loving organisms likely entered the mummy from the glacier environment at the Austrian-Italian border, through body openings, after Ötzi's death. Frank Maixner, Director of the Eurac Institute for Mummy Studies and co-author of the paper, said: "These yeasts have accompanied Ötzi on his long journey through the millennia."

The mummy is "not a static relic, but a dynamic biological system," Maixner further emphasized. A comparison of skin samples from 2010 and 2019 also provides evidence for this: the proportions of different microorganisms have shifted, which, according to the researchers' assessment, indicates that the most cold-adapted among them are still active. Traces of microorganisms specialized in breaking down substances used for disinfection and preservation of the body were also found on the skin.

Discovery Site and Preservation

According to current knowledge, Ötzi was at least 40 years old when he died in the high mountains. His remains were discovered in 1991 by a German hiking couple on the 3200-meter-high Tisenjoch in the Ötztal Alps. The excellent preservation was only possible because the body was covered by snow and ice immediately after death. Today, the mummy lies in a cold chamber at the South Tyrolean Museum of Archaeology in Bolzano – at minus six degrees Celsius and 99 percent humidity.

As early as 2019, a team from Eurac Research had investigated the microbiome in the Ötzi ecosystem for the first time, also detecting bacteria in the digestive tract that are now rarely found in industrialized societies. The wide range of living organism remains now found suggests that it is a "well-protected environment that preserves the ancient microbial signature even after five millennia," the publication states.

Research for Future Generations

Sarhan and his colleagues examined various samples: ice from the surface of the body, meltwater from inside the body, swabs from the gastrointestinal tract, and a soil sample taken at the discovery site in 1991. Additionally, they compared the genetic material with samples from the glacier and the soil from the year of discovery. The team also writes that the 35 years of storage and preservation of the mummy have left their mark.

Elisabeth Vallazza, Director of the South Tyrolean Museum of Archaeology, who was not involved in the study, emphasized: "The preservation conditions of the mummy are very stable today." Nevertheless, further research is necessary to preserve the Iceman for the long term. The anatomy and preservation of the mummy are attributed to Othmar Gaber from Innsbruck, who developed a multi-layered system for Ötzi: the body was wrapped in a sterile surgical cloth, surrounded by plenty of ice, packed in plastic film, and stored at minus six degrees – similar to the conditions in the glacier.

In a Eurac press release, the researchers particularly highlight the discovery of the four yeast variants, which likely entered the mummy from the glacier environment after Ötzi's death. It is now to be clarified "whether the yeasts are descendants of ancient yeasts that maintained their reproduction over the years, or whether they were in an inactive state that was revived after the mummy was thawed," it stated. Until then, "Close microbiological monitoring ensures that the mummy is not damaged."

Much is now known about Ötzi: his blood group, eye color, tattoos, and his presumed last meal. The discovery 35 years ago by hikers on the Tisenjoch attracted worldwide attention. The current study adds another facet to the picture – namely, that the body of the man from the Copper Age still harbors its own, changing microbial ecosystem to this day.