caa a22 4500 44582106X CHVBK 20180317145244.0 cr unu---uuuuu 170323e20110801xx s 000 0 eng 10.1007/s00239-011-9456-1 doi (NATIONALLICENCE)springer-10.1007/s00239-011-9456-1 The Functional Gene Diversity in Natural Populations over Postglacial Areas: The Shaping Mechanisms Behind Genetic Composition of Longnose Dace ( Rhinichthys cataractae ) in Northeastern North America [Elektronische Daten] [Philippe Girard, Bernard Angers] The diversity of functional genes and the related processes are important issues for conservation biology. This is especially relevant for populations that have suffered from demographic reduction as a consequence of the processes of postglacial colonization. In this perspective, the aims of the present study are (1) to quantify the genetic diversity of functional genes and (2) to disentangle the long- and short-term effects of natural selection that shapes genetic diversity from those of drift, mutation, and allopatric fragmentation. This research was conducted using an extensive genetic polymorphism analysis of populations of longnose dace (Rhinichthys cataractae) living over an area once covered by Pleistocene glaciations. The sequence and diversity of one exon of three genes (MHC IIβ, growth hormone, and trypsin) were jointly analyzed with non-coding nuclear loci from 27 populations; these populations were sampled over four major basins of northeastern North America. The survey revealed a surprisingly low allelic richness, especially for the MHC gene, considering the number of individuals and populations sampled. The results suggest that there is a complex mixture of different evolutionary processes shaping the level of polymorphism among longnose dace. While our study underlines the importance of the short-term effects of neutral processes and the major impact of post-glacial colonization on gene diversity, locally dependent balancing selection was detected on MHC. From this perspective, our results support an understanding of the importance of drift on functional gene diversity but also highlight the transient effects of natural selection on allelic composition, even in populations that show drastic reduction of genetic diversity. Springer Science+Business Media, LLC, 2011 Functional genes nationallicence Glaciations nationallicence Fish nationallicence Cyprinidae nationallicence Evolution nationallicence MHC nationallicence Growth hormone nationallicence Trypsin nationallicence Girard Philippe Département de Géographie, Université de Montréal, C.P. 6128, Succ. Centre-Ville, H3C 3J7, Montréal, QC, Canada aut Angers Bernard GRIL, Département des Sciences Biologiques, Université de Montréal, C.P. 6128, Succ. Centre-Ville, H3C 3J7, Montréal, QC, Canada aut Journal of Molecular Evolution Springer-Verlag 73/1-2(2011-08-01), 45-57 0022-2844 73:1-2<45 2011 73 239 https://doi.org/10.1007/s00239-011-9456-1 text/html Onlinezugriff via DOI 1 research-article jats NATIONALLICENCE 856 40 https://doi.org/10.1007/s00239-011-9456-1 text/html Onlinezugriff via DOI NATIONALLICENCE 700 1- Girard Philippe Département de Géographie, Université de Montréal, C.P. 6128, Succ. Centre-Ville, H3C 3J7, Montréal, QC, Canada aut NATIONALLICENCE 700 1- Angers Bernard GRIL, Département des Sciences Biologiques, Université de Montréal, C.P. 6128, Succ. Centre-Ville, H3C 3J7, Montréal, QC, Canada aut NATIONALLICENCE 773 0- Journal of Molecular Evolution Springer-Verlag 73/1-2(2011-08-01), 45-57 0022-2844 73:1-2<45 2011 73 239 Metadata rights reserved Springer special CC-BY-NC licence nationallicence BK010053 XK010053 XK010000 NATIONALLICENCE NATIONALLICENCE NL-springer