Inter-individual genomic heterogeneity within European population isolates

Autoři: Paolo Anagnostou aff001;  Valentina Dominici aff001;  Cinzia Battaggia aff001;  Alessandro Lisi aff001;  Stefania Sarno aff003;  Alessio Boattini aff003;  Carla Calò aff004;  Paolo Francalacci aff004;  Giuseppe Vona aff004;  Sergio Tofanelli aff005;  Miguel G. Vilar aff006;  Vincenza Colonna aff007;  Luca Pagani aff008;  Giovanni Destro Bisol aff001
Působiště autorů: Dipartimento di Biologia Ambientale, Università di Roma “La Sapienza”, Rome, Italy aff001;  Istituto Italiano di Antropologia, Rome, Italy aff002;  Dipartimento di Scienze Biologiche, Geologiche ed Ambientali, Università di Bologna, Bologna, Italy aff003;  Dipartimento di Scienze della Vita e dell’Ambiente, Università di Cagliari, Monserrato, Cagliari, Italy aff004;  Dipartimento di Biologia, Università di Pisa, Pisa, Italy aff005;  National Geographic Society, Washington DC, United States of America aff006;  Institute of Genetics and Biophysics “A. Buzzati-Traverso”, National Research Council (CNR), Naples, Italy aff007;  APE Lab, Department of Biology, University of Padova, Padova, Italy aff008;  Estonian Biocentre, Institute of Genomics, University of Tartu, Tartu, Estonia aff009
Vyšlo v časopise: PLoS ONE 14(10)
Kategorie: Research Article


A number of studies carried out since the early ‘70s has investigated the effects of isolation on genetic variation within and among human populations in diverse geographical contexts. However, no extensive analysis has been carried out on the heterogeneity among genomes within isolated populations. This issue is worth exploring since events of recent admixture and/or subdivision could potentially disrupt the genetic homogeneity which is to be expected when isolation is prolonged and constant over time. Here, we analyze literature data relative to 87,815 autosomal single-nucleotide polymorphisms, which were obtained from a total of 28 European populations. Our results challenge the traditional paradigm of population isolates as structured as genetically (and genomically) uniform entities. In fact, focusing on the distribution of variance of intra-population diversity measures across individuals, we show that the inter-individual heterogeneity of isolated populations is at least comparable to the open ones. More in particular, three small and highly inbred isolates (Sappada, Sauris and Timau in Northeastern Italy) were found to be characterized by levels of inter-individual heterogeneity largely exceeding that of all other populations, possibly due to relatively recent events of genetic introgression. Finally, we propose a way to monitor the effects of inter-individual heterogeneity in disease-gene association studies.

Klíčová slova:

Europe – Haplotypes – Inbreeding – Italy – Molecular genetics – Population genetics – Species diversity – Genomic imprinting


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