Despite being mummified in the icy Austrian landscape 5,300 years ago, Ӧtzi the iceman is continuing to reveal secrets of our ancestral past.
In addition to suffering from the world's first-known case of Lyme disease, a new study has found he was also infected with a common bacterium, Helicobacter pylori, which is present in about half the population today.
Experts say the find could reveal how disease spread at the time of his death, the discovery could even reveal more about the complex movements of the first Europeans.
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A new study has found that Otzi the 5,300 year old ice-mummy was also infected with a common bacterium, Helicobacter pylori. The bacterium is present in about half the population today. The discovery could reveal more about the complex movements of ancient Europeans
Researchers at the European Academy (Eurac) uncovered the genome of H.pylori through analysis of the entire DNA of the contents of Ӧtzi's stomach.
Normally, the bacteria would be found in the lining of the stomach, but as he has been dead for so long, this wasn't possible for Ӧtzi.
As bacteria are transmitted through close contact, they are usually shared by families and communities.
This means that the appearance of their DNA can act as 'bacterial breadcrumbs' for scientist to trace the movements of people thousands of years ago.
The findings also suggest that the bug has been with humans for millennia, and that our evolutionary paths are so intertwined it may have been with us since the beginning of human history.
Scientists believe that there were originally two distinct strains of H.pylori - an African and an Asian strain - which merged to form the modern strain which infects people in Europe today.
But when they analysed the DNA of Ӧtzi's H.pylori, the team made an intriguing discovery.
Rather than being infected with the same strain as Europeans today, the iceman had a strain more closely related to bacteria found in modern Central and South Asia.
It had been assumed that Stone Age people were already infected with the European strain of the bacteria before they settled down, giving up the nomadic life for farming, before Ӧtzi's time in the Copper Age.
But the findings from Ӧtzi turn this theory on its head, indicating that the movements of early Europeans may have been much more complicated than previously believed.
'The recombination of the two types of Helicobacter may have only occurred at some point after Ötzi's era and this shows that the history of settlements in Europe is much more complex than previously assumed,' explained Dr Frank Maixner, a microbiologist at EURAC.
He added: ‘We actually don’t know what kind of people brought this African H.pylori into Europe.
'What we do know is that the signal for this second population, which has come into Europe is strongest in North East Africa.
‘What more than likely happened…is that the North East signal, found in modern day Europeans, had not evolved by the time we left Africa 65,000 years ago.'
The 'Out of Africa' theory holds that the main migration from Africa occurred around 65,000 years ago.
Scientists believe that there were originally two distinct strains of the H.pylori (stock images above) - an African and an Asian strain - which merged to form the modern strain which infects people in Europe today
Last year, a DNA study of modern people from Ethiopia and Egypt suggested that our ancestors first spread east, via the Arabian Peninsula, and entered South Asia long before the 60,000 year mark. They would later have moved westwards, to what is now Europe.
He continued: 'This study, plus others...indicate at least one other migration out of North East Africa, bringing these signals to the Middle East or the fertile crescent.’
The findings also hint that Ӧtzi may even have been sick at the time of his death.
Analysis of the ancient bacterial DNA indicates it was producing toxins which could have been making the iceman ill.
While H.pylori remains relatively quiet in most people, around 10 per cent of those infected will develop complications such as stomach ulcers and gastrointestinal problems, which mostly affect people in old age.
The findings hint that Ӧtzi (pictured) may even have been sick at the time of his death. Analysis of the ancient bacterial DNA indicates it was producing toxins which could have been making the iceman ill. H.pylori can create stomach ulcers and gastrointestinal problems in some people
Dr Albert Zink, a paleobiologist at EURAC and director of the Institute for Mummies and the Iceman, explained: 'Whether Ötzi suffered from stomach problems cannot be said with any degree of certainty, because his stomach tissue has not survived and it is in this tissue that such diseases can be discerned first
When people are infected, their DNA can show lasting signs as they produce immune proteins to battle infection. This immunological 'smoking gun' was found in Ӧtzi.
'We showed the presence of marker proteins which we see today in patients infected with Helicobacter,' said Dr Maixner.
This would mean Ӧtzi's bacteria was expressing virulence factors, pumping out poisons which would likely have placed him within the 10 per cent of people with complications.
Dr Albert Zink, a paleobiologist at EURAC and director of the Institute for Mummies and the Iceman, explained: 'Whether Ötzi suffered from stomach problems cannot be said with any degree of certainty, because his stomach tissue has not survived and it is in this tissue that such diseases can be discerned first.
'Nonetheless, the preconditions for such a disease did in fact exist in Ötzi.'
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