title: The influence of admixture and consanguinity on population genetic diversity in Middle East.
abstract: The Middle East (ME) is an important crossroad where modern humans migrated 'out of Africa' and spread into Europe and Asia. After the initial peopling and long-term isolation leading to well-differentiated populations, the ME also had a crucial role in subsequent human migrations among Africa, Europe and Asia; thus, recent population admixture has been common in the ME. On the other hand, consanguinity, a well-known practice in the ME, often reduces genetic diversity and works in opposition to admixture. Here, we explored the degree to which admixture and consanguinity jointly affected genetic diversity in ME populations. Genome-wide single-nucleotide polymorphism data were generated in two representative ME populations (Arabian and Iranian), with comparisons made with populations worldwide. Our results revealed an overall higher genetic diversity in both ME populations relative to other non-African populations. We identified a much larger number of long runs of homozygosity in ME populations than in any other populations, which was most likely attributed to high levels of consanguineous marriages that significantly decreased both individual and population heterozygosity. Additionally, we were able to distinguish African, European and Asian ancestries in ME populations and quantify the impact of admixture and consanguinity with statistical approaches. Interestingly, genomic regions with significantly excessive ancestry from individual source populations are functionally enriched in olfactory pathways, which were suspected to be under natural selection. Our findings suggest that genetic admixture, consanguinity and natural selection have collectively shaped the genetic diversity of ME populations, which has important implications in both evolutionary studies and medical practices.
authors.affiliation: Chinese Academy of Sciences (CAS) Key Laboratory of Computational Biology, Max-Planck Independent Research Group on Population Genomics, CAS-MPG Partner Institute for Computational Biology (PICB), Shanghai Institutes for Biological Sciences, Chinese Academy of Sciences, Shanghai, China.
authors.forename: Xiong
authors.initials: X
authors.lastname: Yang
authors.affiliation: Department of Biological Sciences, Kuwait University, Safat, Kuwait.
authors.forename: Suzanne
authors.initials: S
authors.lastname: Al-Bustan
authors.affiliation: Chinese Academy of Sciences (CAS) Key Laboratory of Computational Biology, Max-Planck Independent Research Group on Population Genomics, CAS-MPG Partner Institute for Computational Biology (PICB), Shanghai Institutes for Biological Sciences, Chinese Academy of Sciences, Shanghai, China.
authors.forename: Qidi
authors.initials: Q
authors.lastname: Feng
authors.affiliation: Institute of Applied Mathematics, Academy of Mathematics and Systems Science, Chinese Academy of Sciences, Beijing, China.
authors.forename: Wei
authors.initials: W
authors.lastname: Guo
authors.affiliation: Institute of Applied Mathematics, Academy of Mathematics and Systems Science, Chinese Academy of Sciences, Beijing, China.
authors.forename: Zhiming
authors.initials: Z
authors.lastname: Ma
authors.affiliation: Kuwait Medical Genetic Center, Maternity Hospital, Sulaibikhat, Kuwait.
authors.forename: Makia
authors.initials: M
authors.lastname: Marafie
authors.affiliation: Department of Pathology, Faculty of Medicine, Health Sciences Center, Kuwait University, Safat, Kuwait.
authors.forename: Sindhu
authors.initials: S
authors.lastname: Jacob
authors.affiliation: Department of Pathology, Faculty of Medicine, Health Sciences Center, Kuwait University, Safat, Kuwait.
authors.forename: Fahd
authors.initials: F
authors.lastname: Al-Mulla
authors.affiliation: Chinese Academy of Sciences (CAS) Key Laboratory of Computational Biology, Max-Planck Independent Research Group on Population Genomics, CAS-MPG Partner Institute for Computational Biology (PICB), Shanghai Institutes for Biological Sciences, Chinese Academy of Sciences, Shanghai, China.
authors.forename: Shuhua
authors.initials: S
authors.lastname: Xu
mesh_terms: D000465:Algorithms; D001208:Asia / Q000208:ethnology; D044466:Asian People / Q000235:genetics; D003241:Consanguinity; D005060:Europe / Q000208:ethnology; D005260:Female; D005787:Gene Frequency; D014644:Genetic Variation / Q000235:genetics*; D005828:Genetics, Population / Q000379:methods / Q000706:statistics & numerical data*; D015894:Genome, Human / Q000235:genetics; D005838:Genotype; D006801:Humans; D016014:Linear Models; D008297:Male; D008877:Middle East; D008957:Models, Genetic; D020641:Polymorphism, Single Nucleotide; D044465:White People / Q000235:genetics