About 60,000 years ago anatomically modern humans began to move out of Africa and eventually populated the continents of Eurasia and Australia. New genetic evidence confirms that this migration actually happened.
These humans carried with them the bacteria Helicobacter pylori. An international team of microbiologists has traced the origin of the bacteria in modern humans. 520 strains of H. pylori were collected from 51 ethnic groups. Researchers then sequenced seven gene fragments from the DNA of the bacteria. They then sorted out the strains into clusters that showed their genetic and geographic patterns. They found that people from east Africa had the most
kinds of H. pylori suggesting that the bacteria arose in humans in east Africa.
The researchers date the spread of H. pylori to about 60,000 years ago—however, some think it may have been earlier. And it is possible that there was more than one migration. But their findings are consistent with other genetic evidence that modern humans originated in Africa.