Stomach Ulcers Draw A Map Of Human Migration

SMH.Com.Au ^ | 3-10-2003 | Deborah Smith

[blam]

Stomach ulcers draw a map of human migration

By Deborah Smith, Science Writer
March 10 2003

The germ that causes stomach ulcers has been a constant travelling companion throughout tens of thousands of years of human migration.

From the arrival of the first farmers in Europe to the more recent slave trade out of Africa, the tiny spiral bacterium Helicobacter pylori has been hitching a ride inside the travellers' guts, new research shows.

Now the bug could help reveal details about these ancient movements of people.

A genetic analysis of the bacteria found in the stomachs of 27 groups of people around the world, including Australians, has identified five ancestral groups of H. pylori.

White people in Australia, not surprisingly, tend to be infected with European bacteria.

Maoris have a version that arose in East Asia, and the lack of diversity in their bacteria shows that only small numbers of people were able to island-hop all the way to New Zealand from Polynesia about a thousand years ago, the study concludes.

Native Americans have more genetically diverse bacteria derived from the same group as the New Zealanders, revealing the bug first made it to the New World more than 12,000 years ago when people crossed the Bering Strait from Siberia to Alaska.

The research, by an European and American team, is an important contribution to understanding the pathogen, says Australia's leading expert on the bug, Barry Marshall of the University of Western Australia.

Professor Marshall and his colleague Dr Robin Warren revolutionised the treatment of ulcers with their 1983 discovery that they were caused by H. pylori and could be cured with antibiotics.

Professor Marshall's team is studying bacteria from Aboriginal people in Western Australia, to determine whether the germs are of European origin.

The research could explain the mystery of why Aborigines did not get stomach ulcers before colonisation. They may never have been infected by H. pylori, he said. "We suspect there weren't any indigenous strains."

Migrations have usually been traced using archeological finds, by comparing the genes of different peoples, and analysing similarities in languages.

Most bacteria spread quickly between humans. But H. pylori is unusual, because it is passed down within families, usually from mother to child, on shared food or eating implements or in contaminated water.

[blam]

Another tool in our search for the origins of man.

[manna]

Cool.

[Youngblood]

I wonder how closely this data matches the genetic and language patterns? Will they be able to a molecular clock analysis of the diverging bacteria and cross-check it with the estimated timelines they already have? Interesting!

[blam]

"I wonder how closely this data matches the genetic and language patterns? Will they be able to a molecular clock analysis of the diverging bacteria and cross-check it with the estimated timelines they already have? Interesting! "

I assume so....and with the dental studies done by Christie Turner (ASU). Could be revealing.

[gcruse]

Pretty neat when you consider it was just a few years ago that ulcers were thought to be caused by stress. No one had any idea bacteria were involved.

[Judith Anne]

Interestingly, the bismuth in Pepto-Bismol kills the bacteria.

[LiteKeeper]

bump

[Bernard Marx]

Great find!