title: Recent Historical Migrations Have Shaped the Gene Pool of Arabs and Berbers in North Africa.
abstract: North Africa is characterized by its diverse cultural and linguistic groups and its genetic heterogeneity. Genomic data has shown an amalgam of components mixed since pre-Holocean times. Though no differences have been found in uniparental and classical markers between Berbers and Arabs, the two main ethnic groups in the region, the scanty genomic data available have highlighted the singularity of Berbers. We characterize the genetic heterogeneity of North African groups, focusing on the putative differences of Berbers and Arabs, and estimate migration dates. We analyze genome-wide autosomal data in five Berber and six Arab groups, and compare them to Middle Easterns, sub-Saharans, and Europeans. Haplotype-based methods show a lack of correlation between geographical and genetic populations, and a high degree of genetic heterogeneity, without strong differences between Berbers and Arabs. Berbers enclose genetically diverse groups, from isolated endogamous groups with high autochthonous component frequencies, large homozygosity runs and low effective population sizes, to admixed groups with high frequencies of sub-Saharan and Middle Eastern components. Admixture time estimates show a complex pattern of recent historical migrations, with a peak around the 7th century C.E. coincident with the Arabization of the region; sub-Saharan migrations since the 1st century B.C. in agreement with Roman slave trade; and a strong migration in the 17th century C.E., coincident with a huge impact of the trans-Atlantic and trans-Saharan trade of sub-Saharan slaves in the Modern Era. The genetic complexity found should be taken into account when selecting reference groups in population genetics and biomedical studies.
authors.affiliation: Departament de Ciències Experimentals i de la Salut, Institute of Evolutionary Biology (CSIC-UPF), Universitat Pompeu Fabra, Barcelona, Spain.
authors.forename: Lara R
authors.initials: LR
authors.lastname: Arauna
authors.affiliation: Departament de Ciències Experimentals i de la Salut, Institute of Evolutionary Biology (CSIC-UPF), Universitat Pompeu Fabra, Barcelona, Spain.|Genetics Institute, University College London, London, United Kingdom.
authors.forename: Javier
authors.initials: J
authors.lastname: Mendoza-Revilla
authors.affiliation: Departament de Ciències Experimentals i de la Salut, Institute of Evolutionary Biology (CSIC-UPF), Universitat Pompeu Fabra, Barcelona, Spain.|Departamento de Genética, Instituto de Biociências, Universidade Federal do Rio Grande do Sul, Porto Alegre, Brazil.
authors.forename: Alex
authors.initials: A
authors.lastname: Mas-Sandoval
authors.affiliation: Laboratoire de Biologie Cellulaire et Génétique Moléculaire (LBCGM), Université IBNZOHR, Agadir, Morocco.
authors.forename: Hassan
authors.initials: H
authors.lastname: Izaabel
authors.affiliation: Département de Biotechnologie, Faculté des Sciences de la Nature et de la Vie, Université Oran 1 (Ahmad Ben Bella), Oran, Algeria.
authors.forename: Asmahan
authors.initials: A
authors.lastname: Bekada
authors.affiliation: Département de Biotechnologie, Faculté des Sciences de la Nature et de la Vie, Université Oran 1 (Ahmad Ben Bella), Oran, Algeria.
authors.forename: Soraya
authors.initials: S
authors.lastname: Benhamamouch
authors.affiliation: Laboratoire de Génetique, Immunologie et Pathologies Humaines, Faculté des Sciences de Tunis, Campus Universitaire El Manar II, Université El Manar, Tunis, Tunisia.
authors.forename: Karima
authors.initials: K
authors.lastname: Fadhlaoui-Zid
authors.affiliation: The Lebanese American University, Chouran, Beirut, Lebanon.
authors.forename: Pierre
authors.initials: P
authors.lastname: Zalloua
authors.affiliation: Genetics Institute, University College London, London, United Kingdom.
authors.forename: Garrett
authors.initials: G
authors.lastname: Hellenthal
authors.affiliation: Departament de Ciències Experimentals i de la Salut, Institute of Evolutionary Biology (CSIC-UPF), Universitat Pompeu Fabra, Barcelona, Spain.
authors.forename: David
authors.initials: D
authors.lastname: Comas
mesh_terms: D000352:Africa, Northern; D018912:Arabs / Q000235:genetics*; D044383:Black People / Q000235:genetics*; D004272:DNA, Mitochondrial / Q000235:genetics; D005787:Gene Frequency; D005788:Gene Pool; D014644:Genetic Variation; D005828:Genetics, Population; D006239:Haplotypes; D063426:Human Migration; D006801:Humans; D020641:Polymorphism, Single Nucleotide; D044465:White People / Q000235:genetics
chemical_list: D004272:DNA, Mitochondrial
keywords: Berbers; North Africa; admixture; genome wide SNPs; haplotype; population genetics