DNA from people representing 150 ethnic groups from five different African countries was analysed.Credit: nicolas_/ E+/ Getty Images

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A new study published in Science Advances has revealed traces of ancient African empires in the DNA of people living on the continent, that help identify early migration patterns.

Nancy Bird, genetics, evolution and environment researcher at University College London, and colleagues found evidence for migration in vast empires such as Kanem-Bornu, the kingdoms of Aksum and Makuria, and the spread of the Bantu language group.

“Our results emphasise the complexity of Africa’s past. Multiple civilizations throughout history, from thousands of years ago to medieval times, have impacted present day African genetic diversity,” Bird said.

Evidence for migration and ancient African empires has been found in DNA of people living on the continent.Credit: Jeff Israel (ZyMOS), CC BY-SA 3.0, via Wikimedia Commons

The study, the most diverse ever undertaken, analysed DNA from people representing 150 ethnic groups from five different African countries. The multinational research team was also diverse, including geneticists, archeologists, and linguists.

“We demonstrate the large genetic impact of events ranging from the spread of agriculture more than 3000 years ago, to the Arabic expansion into Sudan and Cameroon within the last 800 years,” Bird said.

“We found incredible genetic diversity. For example, by some measures, Cameroon has as much genetic diversity as is seen in the whole of Europe,” she added.

She explained that trade and development of new technologies played a large role in the movement of people—for example, the Kanem Bornu empire was involved in trade across the Sahara, which could explain why we see people from North Africa moving to the area of northern Cameroon.On the other hand, the expansion of Bantu speaking groups more than 4,000 years ago from Cameroon across Sub-Saharan Africa, was associated with new farming and iron working technologies.

The study reiterated the importance of redressing the underrepresentation of African genome data as compared with other world regions.

“This means that lots of genetic diversity—or variety—in the DNA of populations is probably being missed, including genetic variants that contribute to disease susceptibility and health,” Bird said.