Dataset Information

Extensive genome-wide autozygosity in the population isolates of Daghestan.

ABSTRACT: Isolated populations are valuable resources for mapping disease genes, as inbreeding increases genome-wide homozygosity and enhances the ability to map disease alleles on a genetically uniform background within a relatively homogenous environment. The populations of Daghestan are thought to have resided in the Caucasus Mountains for hundreds of generations and are characterized by a high prevalence of certain complex diseases. To explore the extent to which their unique population history led to increased levels of inbreeding, we genotyped >550 000 autosomal single-nucleotide polymorphisms (SNPs) in a set of 14 population isolates speaking Nakh-Daghestanian (ND) languages. The ND-speaking populations showed greatly elevated coefficients of inbreeding, very high numbers and long lengths of Runs of Homozygosity, and elevated linkage disequilibrium compared with surrounding groups from the Caucasus, the Near East, Europe, Central and South Asia. These results are consistent with the hypothesis that most ND-speaking groups descend from a common ancestral population that fragmented into a series of genetic isolates in the Daghestanian highlands. They have subsequently maintained a long-term small effective population size as a result of constant inbreeding and very low levels of gene flow. Given these findings, Daghestanian population isolates are likely to be useful for mapping genes associated with complex diseases.

SUBMITTER: Karafet TM

PROVIDER: S-EPMC4592092 | biostudies-literature | 2015 Oct

REPOSITORIES: biostudies-literature

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Extensive genome-wide autozygosity in the population isolates of Daghestan.

Karafet Tatiana M TM Bulayeva Kazima B KB Bulayev Oleg A OA Gurgenova Farida F Omarova Jamilia J Yepiskoposyan Levon L Savina Olga V OV Veeramah Krishna R KR Hammer Michael F MF

European journal of human genetics : EJHG 20150121 10

Isolated populations are valuable resources for mapping disease genes, as inbreeding increases genome-wide homozygosity and enhances the ability to map disease alleles on a genetically uniform background within a relatively homogenous environment. The populations of Daghestan are thought to have resided in the Caucasus Mountains for hundreds of generations and are characterized by a high prevalence of certain complex diseases. To explore the extent to which their unique population history led to ...[more]

PMID: 25604856

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Dataset Information

Extensive genome-wide autozygosity in the population isolates of Daghestan.

Publications

Extensive genome-wide autozygosity in the population isolates of Daghestan.

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