Increased ultra-rare variant load in an isolated Scottish population impacts exonic and regulatory regions

Autoři: Mihail Halachev aff001;  Alison Meynert aff001;  Martin S. Taylor aff001;  Veronique Vitart aff001;  Shona M. Kerr aff001;  Lucija Klaric aff001;  ;  Timothy J. Aitman aff002;  Chris S. Haley aff001;  James G. Prendergast aff003;  Carys Pugh aff004;  David A. Hume aff005;  Sarah E. Harris aff006;  David C. Liewald aff006;  Ian J. Deary aff006;  Colin A. Semple aff001;  James F. Wilson aff001
Působiště autorů: MRC Human Genetics Unit, MRC IGMM, University of Edinburgh, Crewe Road, Edinburgh, United Kingdom aff001;  Centre for Genomic and Experimental Medicine, MRC IGMM, University of Edinburgh, Crewe Road, Edinburgh, United Kingdom aff002;  The Roslin Institute, University of Edinburgh, Easter Bush, Midlothian, United Kingdom aff003;  Centre for Clinical Brain Sciences, Division of Psychiatry, University of Edinburgh, Royal Edinburgh Hospital, Edinburgh, United Kingdom aff004;  Mater Research Institute, University of Queensland, Woolloongabba, Australia aff005;  Centre for Cognitive Ageing and Cognitive Epidemiology, Department of Psychology, School of Philosophy, Psychology and Language Sciences, University of Edinburgh, George Square, Edinburgh, United Kingdom aff006;  Centre for Global Health Research, Usher Institute of Population Health Sciences and Informatics, University of Edinburgh, Teviot Place, Edinburgh, United Kingdom aff007
Vyšlo v časopise: Increased ultra-rare variant load in an isolated Scottish population impacts exonic and regulatory regions. PLoS Genet 15(11): e32767. doi:10.1371/journal.pgen.1008480
Kategorie: Research Article
doi: 10.1371/journal.pgen.1008480


Human population isolates provide a snapshot of the impact of historical demographic processes on population genetics. Such data facilitate studies of the functional impact of rare sequence variants on biomedical phenotypes, as strong genetic drift can result in higher frequencies of variants that are otherwise rare. We present the first whole genome sequencing (WGS) study of the VIKING cohort, a representative collection of samples from the isolated Shetland population in northern Scotland, and explore how its genetic characteristics compare to a mainland Scottish population. Our analyses reveal the strong contributions played by the founder effect and genetic drift in shaping genomic variation in the VIKING cohort. About one tenth of all high-quality variants discovered are unique to the VIKING cohort or are seen at frequencies at least ten fold higher than in more cosmopolitan control populations. Multiple lines of evidence also suggest relaxation of purifying selection during the evolutionary history of the Shetland isolate. We demonstrate enrichment of ultra-rare VIKING variants in exonic regions and for the first time we also show that ultra-rare variants are enriched within regulatory regions, particularly promoters, suggesting that gene expression patterns may diverge relatively rapidly in human isolates.

Klíčová slova:

Alleles – Europe – Chromatin – Molecular genetics – Population genetics – Promoter regions – Genetic drift – Computer-aided drug design


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