Frozen mummy's gut microbes shed light on human migration

MIAMI • The microbes in the gut of the Iceman, a 5,300-year-old mummy found frozen in a European glacier in 1991, have shed new light on the history of human migration, scientists said on Thursday.

Researchers thawed the mummy of the man, also known as Otzi, who was killed by an arrow when he was between 40 and 50 years old and hiking across the Otztal Alps between modern-day Italy and Austria.

When they tested the contents of his stomach, they found a bacterium called Helicobacter pylori, an age-old pathogen that has evolved into different strains according to the region of the world in which it is found.

About half the people on the planet harbour the bacterium in their stomachs.

It can cause ulcers or gastrointestinal distress and is typically spread among children when they play in the dirt.

While researchers cannot be sure if the Iceman was sick because of the infection, they were intrigued by their analysis of the geographic history of the bacterium.

"Surprisingly, a strain of bacterium in his gut shares ancestry with an Asian strain," said the study in the United States journal, Science. "In contrast to the fact that most modern Europeans harbour a strain ancestral to North African strains."

"This one genome has put things into wonderful perspective for us," said Dr Yoshan Moodley, a researcher at the University of Venda in South Africa.

"We can say now that the waves of migration that brought these African Helicobacter pylori into Europe had not occurred, or at least not occurred in earnest, by the time the Iceman was around."

AGENCE FRANCE-PRESSE

A version of this article appeared in the print edition of The Straits Times on January 09, 2016, with the headline 'Frozen mummy's gut microbes shed light on human migration'. Print Edition | Subscribe