Genome-wide studies of African populations have the potential to reveal powerful insights into the evolution of our species, as these diverse populations have been exposed to intense selective pressures imposed by infectious diseases, diet, and environmental factors. Within Africa, the Sahel Belt extensively overlaps the geographical center of several endemic infections such as malaria, trypanosomiasis, meningitis, and hemorrhagic fevers. We screened 2.5 million single nucleotide polymorphisms in 161 individuals from 13 Sahelian populations, which together with published data cover Western, Central, and Eastern Sahel, and include both nomadic and sedentary groups. We confirmed the role of this Belt as a main corridor for human migrations across the continent. Strong admixture was observed in both Central and Eastern Sahelian populations, with North Africans and Near Eastern/Arabians, respectively, but it was inexistent in Western Sahelian populations. Genome-wide local ancestry inference in admixed Sahelian populations revealed several candidate regions that were significantly enriched for non-autochthonous haplotypes, and many showed to be under positive selection. The DARC gene region in Arabs and Nubians was enriched for African ancestry, whereas the RAB3GAP1/LCT/MCM6 region in Oromo, the TAS2R gene family in Fulani, and the ALMS1/NAT8 in Turkana and Samburu were enriched for non-African ancestry. Signals of positive selection varied in terms of geographic amplitude. Some genomic regions were selected across the Belt, the most striking example being the malaria-related DARC gene. Others were Western-specific (oxytocin, calcium, and heart pathways), Eastern-specific (lipid pathways), or even population-restricted (TAS2R genes in Fulani, which may reflect sexual selection).

• Klíčová slova
• Sahel, admixture, genome-wide diversity, selection,
• MeSH
• acetyltransferasy genetika   MeSH
• genom lidský * MeSH
• haplotypy MeSH
• hemoragické horečky virové genetika   MeSH
• jednonukleotidový polymorfismus MeSH
• krevní skupiny - systém Duffy genetika   MeSH
• lidé MeSH
• malárie genetika   MeSH
• MCM komplex, komponenta 6 genetika   MeSH
• meningitida genetika   MeSH
• migrace lidstva * MeSH
• proteiny buněčného cyklu MeSH
• proteiny genetika   MeSH
• receptory buněčného povrchu genetika   MeSH
• receptory spřažené s G-proteiny genetika   MeSH
• selekce (genetika) * MeSH
• Check Tag
• lidé MeSH
• Publikační typ
• časopisecké články MeSH
• práce podpořená grantem MeSH
• Geografické názvy
• Afrika MeSH
• Názvy látek
• acetyltransferasy MeSH
• ACKR1 protein, human MeSH Prohlížeč
• ALMS1 protein, human MeSH Prohlížeč
• krevní skupiny - systém Duffy MeSH
• MCM komplex, komponenta 6 MeSH
• MCM6 protein, human MeSH Prohlížeč
• NAT8 protein, human MeSH Prohlížeč
• proteiny buněčného cyklu MeSH
• proteiny MeSH
• receptory buněčného povrchu MeSH
• receptory spřažené s G-proteiny MeSH
• TAS2R1 protein, human MeSH Prohlížeč