title: Population genetic structure of the people of Qatar.
abstract: People of the Qatar peninsula represent a relatively recent founding by a small number of families from three tribes of the Arabian Peninsula, Persia, and Oman, with indications of African admixture. To assess the roles of both this founding effect and the customary first-cousin marriages among the ancestral Islamic populations in Qatar's population genetic structure, we obtained and genotyped with Affymetrix 500k SNP arrays DNA samples from 168 self-reported Qatari nationals sampled from Doha, Qatar. Principal components analysis was performed along with samples from the Human Genetic Diversity Project data set, revealing three clear clusters of genotypes whose proximity to other human population samples is consistent with Arabian origin, a more eastern or Persian origin, and individuals with African admixture. The extent of linkage disequilibrium (LD) is greater than that of African populations, and runs of homozygosity in some individuals reflect substantial consanguinity. However, the variance in runs of homozygosity is exceptionally high, and the degree of identity-by-descent sharing generally appears to be lower than expected for a population in which nearly half of marriages are between first cousins. Despite the fact that the SNPs of the Affymetrix 500k chip were ascertained with a bias toward SNPs common in Europeans, the data strongly support the notion that the Qatari population could provide a valuable resource for the mapping of genes associated with complex disorders and that tests of pairwise interactions are particularly empowered by populations with elevated LD like the Qatari.
authors.affiliation: Program in Computational Biology and Medicine, Cornell University, Ithaca, NY 14850, USA.
authors.forename: Haley
authors.initials: H
authors.lastname: Hunter-Zinck
authors.forename: Shaila
authors.initials: S
authors.lastname: Musharoff
authors.forename: Jacqueline
authors.initials: J
authors.lastname: Salit
authors.forename: Khalid A
authors.initials: KA
authors.lastname: Al-Ali
authors.forename: Lotfi
authors.initials: L
authors.lastname: Chouchane
authors.forename: Abeer
authors.initials: A
authors.lastname: Gohar
authors.forename: Rebecca
authors.initials: R
authors.lastname: Matthews
authors.forename: Marcus W
authors.initials: MW
authors.lastname: Butler
authors.forename: Jennifer
authors.initials: J
authors.lastname: Fuller
authors.forename: Neil R
authors.initials: NR
authors.lastname: Hackett
authors.forename: Ronald G
authors.initials: RG
authors.lastname: Crystal
authors.forename: Andrew G
authors.initials: AG
authors.lastname: Clark
mesh_terms: D018912:Arabs / Q000235:genetics*; D044466:Asian People / Q000235:genetics*; D044383:Black People / Q000235:genetics*; D003241:Consanguinity; D005260:Female; D005828:Genetics, Population; D006720:Homozygote; D006801:Humans; D015810:Linkage Disequilibrium; D008297:Male; D009275:Names; D020641:Polymorphism, Single Nucleotide; D025341:Principal Component Analysis; D011780:Qatar