title: Indigenous Arabs are descendants of the earliest split from ancient Eurasian populations.
abstract: An open question in the history of human migration is the identity of the earliest Eurasian populations that have left contemporary descendants. The Arabian Peninsula was the initial site of the out-of-Africa migrations that occurred between 125,000 and 60,000 yr ago, leading to the hypothesis that the first Eurasian populations were established on the Peninsula and that contemporary indigenous Arabs are direct descendants of these ancient peoples. To assess this hypothesis, we sequenced the entire genomes of 104 unrelated natives of the Arabian Peninsula at high coverage, including 56 of indigenous Arab ancestry. The indigenous Arab genomes defined a cluster distinct from other ancestral groups, and these genomes showed clear hallmarks of an ancient out-of-Africa bottleneck. Similar to other Middle Eastern populations, the indigenous Arabs had higher levels of Neanderthal admixture compared to Africans but had lower levels than Europeans and Asians. These levels of Neanderthal admixture are consistent with an early divergence of Arab ancestors after the out-of-Africa bottleneck but before the major Neanderthal admixture events in Europe and other regions of Eurasia. When compared to worldwide populations sampled in the 1000 Genomes Project, although the indigenous Arabs had a signal of admixture with Europeans, they clustered in a basal, outgroup position to all 1000 Genomes non-Africans when considering pairwise similarity across the entire genome. These results place indigenous Arabs as the most distant relatives of all other contemporary non-Africans and identify these people as direct descendants of the first Eurasian populations established by the out-of-Africa migrations.
authors.affiliation: Department of Genetic Medicine, Weill Cornell Medical College, New York, New York 10065, USA;
authors.forename: Juan L
authors.initials: JL
authors.lastname: Rodriguez-Flores
authors.affiliation: Sidra Medical and Research Center, Doha, Qatar; Department of Genetic Medicine, Weill Cornell Medical College-Qatar, Doha, Qatar;
authors.forename: Khalid
authors.initials: K
authors.lastname: Fakhro
authors.affiliation: Department of Genetic Medicine, Weill Cornell Medical College, New York, New York 10065, USA; Department of Biological Statistics and Computational Biology, Cornell University, Ithaca, New York 14850, USA;
authors.forename: Francisco
authors.initials: F
authors.lastname: Agosto-Perez
authors.affiliation: Department of Biological Statistics and Computational Biology, Cornell University, Ithaca, New York 14850, USA;
authors.forename: Monica D
authors.initials: MD
authors.lastname: Ramstetter
authors.affiliation: Department of Biological Statistics and Computational Biology, Cornell University, Ithaca, New York 14850, USA;
authors.forename: Leonardo
authors.initials: L
authors.lastname: Arbiza
authors.affiliation: Department of Genetic Medicine, Weill Cornell Medical College, New York, New York 10065, USA;
authors.forename: Thomas L
authors.initials: TL
authors.lastname: Vincent
authors.affiliation: Department of Genetic Medicine, Weill Cornell Medical College-Qatar, Doha, Qatar;
authors.forename: Amal
authors.initials: A
authors.lastname: Robay
authors.affiliation: Department of Genetic Medicine, Weill Cornell Medical College-Qatar, Doha, Qatar;
authors.forename: Joel A
authors.initials: JA
authors.lastname: Malek
authors.affiliation: Bioinformatics Core, Weill Cornell Medical College-Qatar, Doha, Qatar;
authors.forename: Karsten
authors.initials: K
authors.lastname: Suhre
authors.affiliation: Department of Genetic Medicine, Weill Cornell Medical College-Qatar, Doha, Qatar;
authors.forename: Lotfi
authors.initials: L
authors.lastname: Chouchane
authors.affiliation: Laboratory Medicine and Pathology, Hamad Medical Corporation, Doha, Qatar;
authors.forename: Ramin
authors.initials: R
authors.lastname: Badii
authors.affiliation: Laboratory Medicine and Pathology, Hamad Medical Corporation, Doha, Qatar;
authors.forename: Ajayeb
authors.initials: A
authors.lastname: Al-Nabet Al-Marri
authors.affiliation: Department of Genetic Medicine, Weill Cornell Medical College-Qatar, Doha, Qatar;
authors.forename: Charbel
authors.initials: C
authors.lastname: Abi Khalil
authors.affiliation: Department of Medicine, Hamad Medical Corporation, Doha, Qatar.
authors.forename: Mahmoud
authors.initials: M
authors.lastname: Zirie
authors.affiliation: Department of Medicine, Hamad Medical Corporation, Doha, Qatar.
authors.forename: Amin
authors.initials: A
authors.lastname: Jayyousi
authors.affiliation: Department of Genetic Medicine, Weill Cornell Medical College, New York, New York 10065, USA;
authors.forename: Jacqueline
authors.initials: J
authors.lastname: Salit
authors.affiliation: Department of Biological Statistics and Computational Biology, Cornell University, Ithaca, New York 14850, USA;
authors.forename: Alon
authors.initials: A
authors.lastname: Keinan
authors.affiliation: Department of Biological Statistics and Computational Biology, Cornell University, Ithaca, New York 14850, USA;
authors.forename: Andrew G
authors.initials: AG
authors.lastname: Clark
authors.affiliation: Department of Genetic Medicine, Weill Cornell Medical College, New York, New York 10065, USA;
authors.forename: Ronald G
authors.initials: RG
authors.lastname: Crystal
authors.affiliation: Department of Genetic Medicine, Weill Cornell Medical College, New York, New York 10065, USA; Department of Biological Statistics and Computational Biology, Cornell University, Ithaca, New York 14850, USA;
authors.forename: Jason G
authors.initials: JG
authors.lastname: Mezey
mesh_terms: D000818:Animals; D018912:Arabs / Q000235:genetics*; D044383:Black People / Q000235:genetics*; D016000:Cluster Analysis; D004272:DNA, Mitochondrial / Q000235:genetics; D005787:Gene Frequency; D063426:Human Migration; D006801:Humans; D006824:Hybridization, Genetic; D008390:Markov Chains; D008957:Models, Genetic; D059125:Neanderthals / Q000235:genetics*; D010802:Phylogeny; D025341:Principal Component Analysis; D011780:Qatar; D017422:Sequence Analysis, DNA; D044465:White People / Q000235:genetics*
chemical_list: D004272:DNA, Mitochondrial