PT - JOURNAL ARTICLE AU - Paolo Anagnostou AU - Valentina Dominici AU - Cinzia Battaggia AU - Luca Pagani AU - Miguel Vilar AU - Spencer Wells AU - Davide Pettener AU - Stefania Sarno AU - Alessio Boattini AU - Paolo Francalacci AU - Vincenza Colonna AU - Giuseppe Vona AU - Carla Calò AU - Giovanni Destro Bisol AU - Sergio Tofanelli TI - Overcoming the dichotomy: new insights into the genomic diversity of open and isolated European populations AID - 10.1101/067850 DP - 2016 Jan 01 TA - bioRxiv PG - 067850 4099 - http://biorxiv.org/content/early/2016/08/05/067850.short 4100 - http://biorxiv.org/content/early/2016/08/05/067850.full AB - Human populations are often dichotomized into “isolated” and “open” using cultural and/or geographical barriers to gene flow as differential criteria. Although widespread, the use of these alternative categories could obscure further heterogeneity due to inter-population differences in effective size, growth rate, and timing or amount of gene flow. We compared intra and interpopulation variation measures combining novel and literature data relative to 87,818 autosomal SNPs in 14 open populations and 10 geographic and/or linguistic European isolates. Patterns of intra-population diversity were found to vary significantly more among isolates, probably due to differential levels of drift and inbreeding. The relatively large effective size estimated for some population isolates challenges the generalized view that they originate from small founding groups. Principal component scores based on measures of intra-population variation of isolated and open populations turned out to be distributed along a sort of continuum, with an area of intersection between the two groups. Patterns of inter-population diversity were even closer, as we were able to detect some differences between population groups only for a few multidimensional scaling dimensions. Therefore, different lines of evidence suggest that dichotomizing human populations into open and isolated fails to capture the actual relations among their genomic features.