Using population genomic tools, researchers at Johns Hopkins Medicine, the Institute of Archaeology of the Czech Academy of Sciences, Prague, and Uppsala University in Sweden, mapped the genetic background and ancestry of a nomadic pastoral group in Africa to the Green Sahara period, the prehistoric time between 5,000 and 11,000 years ago.
During the Green Sahara period, a wetter climate transformed the Sahara Desert into a hospitable environment that allowed early pastoral groups, including the Fulani, to thrive.
The researchers, led by Cesar Fortes-Lima, Ph.D., an instructor in the Department of Genetic Medicine at the Johns Hopkins University School of Medicine, set out to determine where Fulani ancestors originated and whether the Fulani share genetic ancestry with other African groups.
Overall, genetic research on populations provides a better understanding of migration, genetic exchange, cultural patterns over time, and the impact of these factors on human health. Fortes-Lima's fields of population genetics and evolutionary biology are important for understanding shared genetic patterns between and within human groups worldwide.
The nomadic Fulani, whose origins have long been debated by anthropologists, linguists, and geneticists, have an estimated population of 40 million people worldwide and are largely underrepresented in genomic research, says Fortes-Lima.
The findings, published in February in the American Journal of Human Genetics, expand on previous studies that analyzed the genetic history of smaller subgroups of the Fulani in particular regions. The Fulani, a large nomadic pastoral group that travels across the Sahel belt with their domesticated livestock animals, live in scattered locations from Africa's western coast to the middle of the continent.
By analyzing the DNA of 460 Fulani people encompassing 18 populations from nine African countries across the Sahel belt, the researchers revealed a shared genetic component among all Fulani populations, which can be traced back to hunter-gatherers, known as Iberomaurusians, who lived in North Africa during the Stone Age, Fortes-Lima says.
Beyond their complex genetic ancestry, Fulani people have adaptations to live in the arid Sahel belt environments, which have significant biological and medical implications. For example, the Fulani share a genetic trait that helps them process lactose, a sugar in cow's milk. Fulani, North African and East African populations are among the few groups in Africa to have this trait. The Fulani and North Africans have the same genetic variant, likely due to gene flow between them, while Eastern Africans have different genetic variants, Fortes-Lima says.
"Further research documenting the genomic diversity of more groups in Africa can help to advance scientific research, health equity and our understanding of human history," says Fortes-Lima. "For instance, individuals whose African ancestors were forced to migrate to the United States during the transatlantic slave trade may have shared genetic links to the Fulani, and the insights about the Fulani presented in our study can help to investigate those links broken during that period."
In addition to Fortes-Lima, study contributors are Mame Diallo, Václav Janoušek and Viktor Černý from the Institute of Archaeology of the Czech Academy of Sciences, and Carina Schlebusch from Uppsala University in Sweden.
