Ancient African empires’ impact on migration revealed by genetics

Traces of ancient empires that stretched across Africa remain in the DNA of people living on the continent, reveals a new genetics study led by UCL researchers. Published in Science Advances , the collaboration between UCL geneticists working alongside anthropologists, archaeologists, historians and linguists in Africa and beyond found evidence for when different peoples intermixed across the continent. Their findings indicate migration linked to vast empires such as the Kanem-Bornu and the kingdoms of Aksum and Makuria, as well as the spread of the Bantu language group, now spoken by close to one in four Africans. Much of their study focused on Cameroon, where the researchers had collected the most genomes, and they show that the central African country has as much genetic diversity by some measures as the whole of Europe. Representing one of the most densely sampled studies of African genomes to date, the study used new genetic data from more than 1,300 individuals from 150 ethnic groups from across Africa (primarily Cameroon, Republic of the Congo, Ghana, Nigeria, and Sudan, plus some more in southern Africa). By comparing genetic variation patterns between present-day people from different parts of Africa and elsewhere, they identified when intermixing occurred between different ethnic groups, which likely indicates relatively high migration at specific times and places. First author of the study, PhD candidate Nancy Bird (UCL Genetics Institute) said: "We found evidence that roughly 600 years ago people from north and east Africa were migrating into the region of the Kanem-Bornu Empire, likely reflecting its huge impact on trade across Africa.