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Cuveliers E.L.,Charles University | Volckaert F.A.M.,Charles University | Rijnsdorp A.D.,Institute for Marine Resources and Ecological Studies | Rijnsdorp A.D.,Wageningen University | And 4 more authors.
Molecular Ecology | Year: 2011

Heavy fishing and other anthropogenic influences can have profound impact on a species' resilience to harvesting. Besides the decrease in the census and effective population size, strong declines in mature adults and recruiting individuals may lead to almost irreversible genetic changes in life-history traits. Here, we investigated the evolution of genetic diversity and effective population size in the heavily exploited sole (Solea solea), through the analysis of historical DNA from a collection of 1379 sole otoliths dating back from 1957. Despite documented shifts in life-history traits, neutral genetic diversity inferred from 11 microsatellite markers showed a remarkable stability over a period of 50 years of heavy fishing. Using simulations and corrections for fisheries induced demographic variation, both single-sample estimates and temporal estimates of effective population size (N e) were always higher than 1000, suggesting that despite the severe census size decrease over a 50-year period of harvesting, genetic drift is probably not strong enough to significantly decrease the neutral diversity of this species in the North Sea. However, the inferred ratio of effective population size to the census size (N e/N c) appears very small (10 -5), suggesting that overall only a low proportion of adults contribute to the next generation. The high N e level together with the low N e/N c ratio is probably caused by a combination of an equalized reproductive output of younger cohorts, a decrease in generation time and a large variance in reproductive success typical for marine species. Because strong evolutionary changes in age and size at first maturation have been observed for sole, changes in adaptive genetic variation should be further monitored to detect the evolutionary consequences of human-induced selection. © 2011 Blackwell Publishing Ltd. Source


Larmuseau M.H.D.,Laboratory of Forensic Genetics and Molecular Archaeology | Larmuseau M.H.D.,Catholic University of Leuven | Van Geystelen A.,Laboratory of Forensic Genetics and Molecular Archaeology | Van Oven M.,Rotterdam University | And 2 more authors.
American Journal of Physical Anthropology | Year: 2013

In this article, we promote the implementation of extensive genealogical data in population genetic studies. Genealogical records can provide valuable information on the origin of DNA donors in a population genetic study, going beyond the commonly collected data such as residence, birthplace, language, and self-reported ethnicity. Recent studies demonstrated that extended genealogical data added to surname analysis can be crucial to detect signals of (past) population stratification and to interpret the population structure in a more objective manner. Moreover, when in-depth pedigree data are combined with haploid markers, it is even possible to disentangle signals of temporal differentiation within a population genetic structure during the last centuries. Obtaining genealogical data for all DNA donors in a population genetic study is a labor-intensive task but the vastly growing (genetic) genealogical databases, due to the broad interest of the public, are making this job more time-efficient if there is a guarantee for sufficient data quality. At the end, we discuss the advantages and pitfalls of using genealogy within sampling campaigns and we provide guidelines for future population genetic studies. © 2013 Wiley Periodicals, Inc. Source


Raeymaekers J.A.M.,Catholic University of Leuven | Raeymaekers J.A.M.,University of Basel | Konijnendijk N.,Catholic University of Leuven | Larmuseau M.H.D.,Catholic University of Leuven | And 4 more authors.
Molecular Ecology | Year: 2014

Genes with major phenotypic effects facilitate quantifying the contribution of genetic vs. plastic effects to adaptive divergence. A classical example is Ectodysplasin (Eda), the major gene controlling lateral plate phenotype in three-spined stickleback. Completely plated marine stickleback populations evolved repeatedly towards low-plated freshwater populations, representing a prime example of parallel evolution by natural selection. However, many populations remain polymorphic for lateral plate number. Possible explanations for this polymorphism include relaxation of selection, disruptive selection or a balance between divergent selection and gene flow. We investigated 15 polymorphic stickleback populations from brackish and freshwater habitats in coastal North-western Europe. At each site, we tracked changes in allele frequency at the Eda gene between subadults in fall, adults in spring and juveniles in summer. Eda genotypes were also compared for body size and reproductive investment. We observed a fitness advantage for the Eda allele for the low morph in freshwater and for the allele for the complete morph in brackish water. Despite these results, the differentiation at the Eda gene was poorly correlated with habitat characteristics. Neutral population structure was the best predictor of spatial variation in lateral plate number, suggestive of a substantial effect of gene flow. A meta-analysis revealed that the signature of selection at Eda was weak compared to similar studies in stickleback. We conclude that a balance between divergent selection and gene flow can maintain stickleback populations polymorphic for lateral plate number and that ecologically relevant genes may not always contribute much to local adaptation, even when targeted by selection. © 2013 John Wiley & Sons Ltd. Source


Larmuseau M.H.D.,Laboratory of Forensic Genetics and Molecular Archaeology | Larmuseau M.H.D.,Catholic University of Leuven | Vanoverbeke J.,Catholic University of Leuven | Gielis G.,University of Arts | And 4 more authors.
Heredity | Year: 2012

Patrilineal heritable surnames are widely used to select autochthonous participants for studies on small-scale population genetic patterns owing to the unique link between the surname and a genetic marker, the Y-chromosome (Y-chr). Today, the question arises as to whether the surname origin will be informative on top of in-depth genealogical pedigrees. Admixture events that happened in the period after giving heritable surnames but before the start of genealogical records may be informative about the additional value of the surname origin. In this context, an interesting historical event is the demic migration from French-speaking regions in Northern France to the depopulated and Dutch-speaking region Flanders at the end of the sixteenth century. Y-chr subhaplogroups of individuals with a French/Roman surname that could be associated with this migration event were compared with those of a group with autochthonous Flemish surnames. Although these groups could not be differentiated based on in-depth genealogical data, they were significantly genetically different from each other. Moreover, the observed genetic divergence was related to the differences in the distributions of main Y-subhaplogroups between contemporary populations from Northern France and Flanders. Therefore, these results indicate that the surname origin can be an important feature on top of in-depth genealogical results to select autochthonous participants for a regional population genetic study based on Y-chromosomes. © 2012 Macmillan Publishers Limited All rights reserved. Source


Larmuseau M.H.D.,Laboratory of Forensic Genetics and Molecular Archaeology | Larmuseau M.H.D.,Catholic University of Leuven | Van Geystelen A.,Catholic University of Leuven | Kayser M.,Rotterdam University | And 3 more authors.
Forensic Science International: Genetics | Year: 2015

Currently, several different Y-chromosomal phylogenies and haplogroup nomenclatures are presented in scientific literature and at conferences demonstrating the present diversity in Y-chromosomal phylogenetic trees and Y-SNP sets used within forensic and anthropological research. This situation can be ascribed to the exponential growth of the number of Y-SNPs discovered due to mostly next-generation sequencing (NGS) studies. As Y-SNPs and their respective phylogenetic positions are important in forensics, such as for male lineage characterization and paternal bio-geographic ancestry inference, there is a need for forensic geneticists to know how to deal with these newly identified Y-SNPs and phylogenies, especially since these phylogenies are often created with other aims than to carry out forensic genetic research. Therefore, we give here an overview of four categories of currently used Y-chromosomal phylogenies and the associated Y-SNP sets in scientific research in the current NGS era. We compare these categories based on the construction method, their advantages and disadvantages, the disciplines wherein the phylogenetic tree can be used, and their specific relevance for forensic geneticists. Based on this overview, it is clear that an up-to-date reduced tree with a consensus Y-SNP set and a stable nomenclature will be the most appropriate reference resource for forensic research. Initiatives to reach such an international consensus are therefore highly recommended. © 2014 Elsevier Ireland Ltd. All rights reserved. Source

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