Scientists thaw 5,300-year-old mummy to study ancient gut bacteria

Scientists say the famous "Iceman," a 5,300-year-old European mummy, may have been feeling a little ill on the day an unknown assailant chased him through the Alps, shot an arrow into his artery and killed him.

See Full Article

A recent study shows the Copper-Age European, who is also known as Oetzi, carried a viral strain of Helicobacter pylori bacteria in his stomach, a discovery that scientists say sheds important light on both the Iceman's health and the history of human migration.

The findings were published in the journal Science on Thursday.

According to the study authors, Helicobacter pylori is one of the most common and ancient human pathogens.

Scientists estimate the bacteria has been infecting humans for at least 100,000 years. But researcher say the Iceman sample is the oldest Helicobacter pylori DNA they've ever examined in depth.

"That is why this genome is so special," study co-author Yoshan Moodley, a genetics and biology professor at South Africa's University of Venda, told reporters in a teleconference on Wednesday. "It allows us this absolutely unique window into the Copper Age. We don't have to infer it. We can see."

Helicobacter pylori can cause ulcers or gastric carcinoma, but fewer than 10 per cent of carriers actually suffer from these symptoms.

Because of this, it's unknown if Iceman actually felt the effects of his bacterial infection.

"We can't be 100 per cent sure that he really suffered from gastric disease," Moodley said. "We have clear evidence that he had immune reactions, but we can't really say to what extent."

Thawing the Iceman and extracting the samples

The Iceman's remains are usually kept in Italy's South Tyrol Museum of Archeology, where the museum imitates the Alpine conditions in which the body was preserved until hikers found it in 1991.

But in order to extract and examine bacteria from the Iceman's stomach, scientists had to temporarily thaw the mummy.

Researchers did this in a tightly controlled environment, the Iceman wasn't harmed in the process and he was later refrozen, says study co-author Albert Zink, the scientific director at the Institute for Mummies and the Iceman.

Once the body was defrosted, researchers accessed the stomach through a previously-made incision, and extracted samples from his gastrointestinal tract.

In these samples, they found the presence of Helicobacter pylori, and were able to reconstruct the bacteria's genome and examine its genetic makeup.

This analysis, the study says, led to a "surprising" new understanding of ancient Europeans' origins.

Using Helicobacter pylori to trace human migration

Because Helicobacter pylori has existed in humans for so long, scientists say its evolution reflects the way human populations have grown, migrated and changed.

"Helicobacter pylori's worldwide population structure is almost literally a mirror image of human populations," Moodley said. "So we use them as a surrogate for what humans were doing at various stages of prehistory."

Modern strains of the bacteria are categorized according to geographic location, and can be traced back to different ancestral sources.

The modern Helicobacter pylori strain in Europe, for example, comes from a combination of ancestral bacteria from Asia and Africa.

But scientists were surprised to find that the ancient bacteria in the Iceman's stomach showed only the Asian strain, not a mixture with the African variation.

Scientists say this suggests a wave of human migration arrived in Europe from Africa sometime after the Iceman's death, introducing the North African strain of bacteria to the population.

"The wave of migration that brought the African Helicobacter pylori into Europe had not occurred, or had not occurred in earnest, by the time the Iceman was alive," Moodley concluded.

'Paleomicrobiology' and examining other mummy guts

Now that scientists have successfully extracted and reconstructed bacteria from the Iceman, they hope to use similar techniques to explore other ancient gut bacteria.

"One thing we definitely want to do is to expand our investigation to other mummies," Zink said on Wednesday.

He said he and his co-researchers have already been in touch with colleagues in Northern Europe, South America and Asia, and also hope to trace the paths of ancient bacteria in Siberia.

Eventually, Zink said, he hopes this could open the doors to a "totally new" field of research, which he dubs "paleomicrobiology."



Advertisements

Latest Tech & Science News

  • Public viewing of John Glenn in Ohio to extend for 8 hours

    Tech & Science CTV News
    COLUMBUS, Ohio -- Members of the public will be given eight hours Friday to pay their respects to John Glenn as the late astronaut-hero lies in state at Ohio's capitol building. A spokesman said Saturday that Glenn would lie in repose in the Statehouse Rotunda from noon to 8 p.m. Source
  • The Last Guardian review: Fumito Ueda’s PS4 game a thing of beauty

    Tech & Science Toronto Sun
    Nine years is a long time to wait for something. And nine years is an especially long time to anticipate something, if you can appreciate the difference. The Last Guardian, out this week for the PlayStation 4, was officially announced nine years ago. Source
  • Down but not out: BlackBerry still has projects up its sleeve

    Tech & Science CTV News
    In spite of meager sales figures, BlackBerry could soon release a new smartphone, once again running Google's Android OS and with a physical keyboard. The firm has also developed an innovative Internet of Things security solution for business. Source
  • Samsung to disable Note 7 phones in recall effort

    Tech & Science CTV News
    Samsung announced Friday it would disable its Galaxy Note 7 smartphones in the U.S. market to force remaining owners to stop using the devices, which were recalled for safety reasons. The South Korean electronics giant, the world's biggest smartphone vendor, said 93 percent of Note 7 phones in the United States had been returned to the company after its recall earlier this year, which came amid reports of devices exploding or catching fire. Source
  • Climate change film 'An Inconvenient Truth' gets a sequel

    Tech & Science CTV News
    LOS ANGELES - Al Gore's climate change documentary, "An Inconvenient Truth," is getting a sequel. Paramount Pictures said Friday the follow-up to the Oscar-winning original will premiere at next January's Sundance Film Festival. In the new documentary, former Vice-President Gore examines global warming's escalation and the solutions at hand, Paramount said. Source
  • 'This game is not over yet:' Arctic researcher has hope we can turn corner on climate change

    Tech & Science CBC News
    John England, the Canadian scientist who this week won the $50,000 Weston Family prize for northern research, compares the Arctic to a "great behavioural bath" — in which immersion can help one shed the accumulated "barnacles" of modern life. Source
  • World's oldest seabird, a 66-year-old albatross, expecting chicks

    Tech & Science CTV News
    This Nov. 28, 2015 photo provided by the U.S. Fish and Wildlife Service shows the world's oldest known seabird, Wisdom, right, tending to an egg she laid, with her mate, at Midway Atoll, a wildlife refuge about 1,200 miles northwest of Honolulu. Source
  • Scientists hunt for carbon monoxide poisoning antidote

    Tech & Science CBC News
    Scientists are on the trail of a potential antidote for carbon monoxide poisoning, an injected "scavenger" that promises to trap and remove the gas from blood within minutes. It's very early-stage research — but a reminder that, however it turns out, there are steps people should take now to protect themselves from this silent killer. Source
  • Virtual reality a sickening experience

    Tech & Science CBC News
    A new study has found that many people — especially women — who use virtual reality 3D goggles, experience motion sickness after 15 minutes of use. As the technology becomes more common, wearers will have to adapt to the new sensations the way sailors and astronauts do on the seas and in space. Source
  • Third-ever natural quasicrystal found in Siberian meteorite

    Tech & Science CTV News
    Scientists have discovered an incredibly rare and unusual crystal, known as a quasicrystal, in a meteorite previously found in Siberia in 2011. While there are over 100 lab-made quasicrystals, this crystal, identified in a new paper published Thursday in Scientific Reports, is the first quasicrystal to be found in naturethat wasn’t previously also discovered in a lab. Source