The frozen belly of Ötzi the iceman found in 1991 in the Italian Alps and lived during the Copper Age about 5,300 years ago-has just check that the traveler about 46 years old and brown eyes suffered the effects of bloating because of a bacterium that today gives clues about the possible movement of the human population.
According to a study published today in the journal Science , a group of European researchers, Americans and South Africans found in the stomach and intestines of Ötzi a virulent strain of Helicobacter pylori , which could have ill and left defenseless against the arrow He struck him and caused his death. He died bled an autumn afternoon, at 3,200 meters high.
As the human preferred host for the bacteria, this organism has become a witness of all their movements, their migrations through history while adapting to the new conditions that have generated mutations and different genotypes.
This strain, explained Yoshan Moodley, Professor, Department of Zoology, South African university of Venda, belonged to an extinct population but closely related but not equal to that currently carry the inhabitants of northern India and other parts of South Asia. “This was a great discovery,” he said, as it showed that the 50:50 mixture of bacterial strains Asia and northeast Africa Europeans now carry took place after the existence of Ötzi, when massive waves of migrations occurred and significant population growth.
Thaw Mummy
Get Ötzi’s stomach samples was not easy. It began when scientists in the radiology department of the Central Hospital of Bolzano in Italy, achieved a CT scanner (CT) scan of the mummy, which revealed the presence of this body. If samples were obtained would be possible to answer questions about what they had eaten in the last hour or meet microorganisms inhabiting his body.
“The first challenge of the project was to obtain these samples without harming the mummy” said biologist and anthropologist Albert Zink, head of the Institute for Mummies and the Iceman in Bolzano. It was necessary to defrost, make an incision in the abdomen and take samples of both the stomach wall, to assess the conditions of the fabric, and the inside of the organ. With the support of the Department of Microbiology and Ecosystem at the University of Vienna (Austria) Science, had access to their intestinal tract and, using sophisticated DNA sequencers, detected the bacteria.
To confirm that it was ancient DNA and rule out the possibility that there were contaminated with modern strains, they had to develop specific software tools. At this stage the project had to separate the genetic material found like food, other pathogens and terrestrial bacteria, which was like “looking for a needle in a haystack”, according to biochemist Thomas Rattei, chief of the Division of Computer Systems Austrian university. And they reconstructed the genome of prehistoric bacteria and found that it was most likely the culprit of inflammation in the gastric mucosa of Ötzi.
“This is the oldest known pathogen that has been sequenced,” said Moodley, and promotes an emerging scientific field in which they want to penetrate deep. The paleomicrobiología, the study of ancient organisms and the diseases that caused in the past
What now
“The study of the population structure of the M. pylori helps us understand human evolution, “continued Moodley. As this bacteria exists only in the human stomach, and because their DNA mutates more frequently than ours, we may have a clearer idea of the migration of the population. Genetic analysis of these strains provides increasingly accurate information on what has been the story map of the geography of man.
From this study, Zink told El Espectador to extend the investigation of the presence of M. pylori to other regions. And they are in contact with colleagues from Southern and Northern Europe who have studied stomachs and intestines of mummies America. They have ruled out working with Egyptian mummies, as in the process of mummification old extracted these organs of human body.
A Ötzi it never crossed my mind that 5300 years after the day he was killed brutally by his enemy in the Alpine heights, his body would raise some questions that reveal scientists of the century.
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