Bight of Benin: a maternal perspective of four Beninese populations and their genetic implications on the American populations of African ancestry

The understanding of the first movements of the ancestral populations within the African continent is still unclear, particularly in West Africa, due to several factors that have shaped the African genetic pool across time. To improve the genetic representativeness of the Beninese population and to better understand the patterns of human settlement inside West Africa and the dynamics of peopling of the Democratic Republic of Benin, we analyzed the maternal genetic variation of 193 Beninese individuals belonging to Bariba, Berba, Dendi, and Fon populations. Results support the oral traditions indicating that the western neighbouring populations have been the ancestors of the first Beninese populations, and the extant genetic structure of the Beninese populations is most likely the result of admixture between populations from neighbouring countries and native people. The present findings highlight how the Beninese populations contributed to the gene pool of the extant populations of some American populations of African ancestry. This strengthens the hypothesis that the Bight of Benin was not only an assembly point for the slave trade during the Trans-Atlantic Slave Trade but also an important slave trapping area.