| 1. |
- Andreasen, Katarina
(författare)
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Implications of molecular systematic analyses on the conservation of rare and threatened taxa : contrasting examples from Malvaceae
- 2005
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Ingår i: Conservation Genetics. - : Springer Science and Business Media LLC. - 1566-0621 .- 1572-9737. ; 6:3, s. 399-412
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Tidskriftsartikel (refereegranskat)abstract
- Systematic research provides essential evidence for setting conservation priorities for rare and endangered taxa. Phylogenetic analyses can identify cryptic, genetically distinct lineages as well as actively interbreeding, and hence, non-distinctive lineages earlier perceived as separate taxa. A major aim of this study was to identify genetically distinct, rare lineages within two Malvaceae sister-genera, Sidalcea and Eremalche. The focus was two taxon-pairs each consisting of one rare and one more common taxon. The results demonstrate that even within two closely related genera, with a large number of rare taxa, molecular phylogenetic analyses can reveal contrasting degrees of evolutionary divergence and thus contrasting conservation implications for threatened taxa. Contrary to expectations, the substitution rate in the nuclear ribosomal transcribed spacers for annualEremalche did not correspond to the faster evolutionary rate of annuals – compared to perennials – detected earlier within Sidalcea. Branch lengths in the (annual) Eremalche clade were shorter than those of annual members of Sidalcea. The phylogenetic analyses showed that the rare and endangered S. keckii and E. kernensis each are most closely related to a common species that has been regarded as insufficiently distinct to warrant separate taxonomic status. An additional aim of the study was to test the utility of the Phylogenetic Diversity (PD) measure to formalize the procedure of prioritizing conservation efforts. The measure demonstrated S. keckii (but not E. kernensis) to be genetically distinct from its closest relative and a good candidate for conservation. The PD measure was earlier used for assessing conservation priorities for areas, but proved useful to more objectively suggest conservation priorities among threatened taxa. Because this measure is calculated directly from the data, it retains more character information and gives a better representation of genetic diversity than other measures relying on tree topologies.
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| 2. |
- Arrendal, Johanna, et al.
(författare)
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Reliability of noninvasive genetic census of otters compared to field censuses
- 2007
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Ingår i: Conservation Genetics. - : Springer Science and Business Media LLC. - 1566-0621 .- 1572-9737. ; 8:5, s. 1097-1107
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Tidskriftsartikel (refereegranskat)abstract
- Conservation and management actions are often highly dependent on accurate estimations of population sizes. However, these estimates are difficult to obtain for elusive and rare species. We compared two census methods for Eurasian otter: snow tracking and noninvasive genetic census based on the genotyping of faecal samples. With the noninvasive genetic census we detected the presence of almost twice as many otters as with snow tracking (23 and 10–15, respectively), and mark-recapture estimates based on the genetic census indicated that the real number of otters could be even higher. Our results indicate that snow tracking tends to underestimate the number of individuals and also that it is more susceptible to subjective assessment. We compared the strengths and weaknesses of the two methods.
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| 3. |
- Björnerfeldt, Susanne, et al.
(författare)
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Evaluation of methods for single hair DNA amplification
- 2007
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Ingår i: Conservation Genetics. - : Springer Science and Business Media LLC. - 1566-0621 .- 1572-9737. ; 8:4, s. 977-981
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Tidskriftsartikel (refereegranskat)abstract
- Because of the low amount of DNA in single hairs, it may be difficult to obtain reliable genotypes for forensic and conservation genetics studies. We therefore compared different methods for reliably genotyping single hair samples. Our results indicate that preliminary whole genome amplification can increase the likelihood of successfully genotyping a single hair compared to other commonly used protocols. The difference between the methods is small for single locus comparisons, but it becomes more important in multi-locus comparisons. The economic and time costs of the whole genome amplification may prevent its large-scale use in non-invasive monitoring programs. Nevertheless, it may be a very useful approach for the analysis of especially valuable samples.
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| 4. |
- Gardeström, J., et al.
(författare)
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Characterization of six microsatellite loci in the Baltic blue mussel Mytilus trossulus and cross-species amplification in North Sea Mytilus edulis
- 2008
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Ingår i: Conservation Genetics. - : Springer Science and Business Media LLC. - 1566-0621 .- 1572-9737. ; 9:4, s. 1003-1005
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Tidskriftsartikel (refereegranskat)abstract
- The blue mussel Mytilus trossulus occurs in the Pacific and in the North Atlantic. We developed and characterized six microsatellite loci for Baltic M. trossulus. Seventeen microsatellite loci were screened, of which six were polymorphic. The number of alleles among 50 individuals ranged from 3 to 13 and the observed and expected heterozygosity were 0.09-0.46 and 0.34-0.86, respectively. The loci were also tested for cross amplification in M. edulis, in which four of the six microsatellite loci were successfully amplified.
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| 5. |
- Graves, JA, et al.
(författare)
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Microsatellite and mtDNA analysis of the population structure of grey seals (Halichoerus grypus) from three breeding areas in the Baltic Sea
- 2009
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Ingår i: Conservation Genetics. - : Springer Science and Business Media LLC. - 1566-0621 .- 1572-9737. ; 10, s. 59-68
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Tidskriftsartikel (refereegranskat)abstract
- The growing number of grey seals in the Baltic Sea has led to a dramatic increase in interactions between seals and fisheries. The conflict has become such a problem that hunting was introduced in Finland in 1998 and the Swedish Environment Protection Agency recommended a cull of grey seals starting in 2001. Culling has been implemented despite the lack of data on population structure. Low levels of migration between regions would mean that intensive culling in specific geographic areas would have disproportionate effects on local population structure and genetic diversity. We used eight microsatellite loci and a 489 bp section of the mtDNA control region to examine the genetic variability and differentiation between three breeding sites in the Baltic Sea and two in the UK. We found high levels of genetic variability in all sampled Baltic groups for both the microsatellites and the control region. There were highly significant differences in microsatellite allele frequencies between all three Baltic breeding sites and between the Baltic sites and the UK sites. However, there were no significant differences in mtDNA control region haplotypes between the Baltic sites. This genetic substructure of the Baltic grey seal populations should be taken into consideration when managing the seal population to prevent the hunting regime from having an adverse effect on genetic diversity by setting hunting quotas separately for the different subpopulations.
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| 6. |
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| 7. |
- Hansson, Bengt, et al.
(författare)
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Heterozygosity-fitness correlations within inbreeding classes : Local or genome-wide effects?
- 2008
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Ingår i: Conservation Genetics. - : Springer Science and Business Media LLC. - 1566-0621 .- 1572-9737. ; 9:1, s. 73-83
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Tidskriftsartikel (refereegranskat)abstract
- Marker-based studies of inbreeding may lead to an enhanced understanding of inbreeding depression in natural populations, which is a major concern in conservation genetics. Correlations between marker heterozygosity and variation in fitness-associated traits-'heterozygosity-fitness correlations' (HFCs)-are of particular importance and have been widely applied in natural populations. In partially inbred populations, HFCs can be driven by selection against inbred individuals and thus reflect inbreeding depression. However, other explanations for HFCs also exist, such as functional effects of the markers per se or that the markers reveal selection on linked fitness genes due to extended linkage disequilibrium (LD) in the population. Accordingly, HFCs do not only arise in partially inbred populations, they may also occur within inbreeding classes such as families, i.e. in situations when there is no variation in the inbreeding coefficient. In this study we focus on the importance of LD for within-family HFCs, thereby aiming at enhancing our general understanding of HFCs. For non-coding markers, within-family HFCs have been proposed to be caused in two ways: either by 'local effects' at linked fitness genes in LD with the markers, or by 'general effects' due to a correlation between proportion of heterozygous markers (H M ) and heterozygosity at genome-wide distributed fitness genes (H GW ). To evaluate these contrasting hypotheses for within-family HFCs, we analysed simulated data sets of sexually reproducing populations with varying levels of LD. The results confirmed that segregation induces variation in both H M and H GW at a fixed level of inbreeding, as expected, the variation in H M declined with increasing number of markers, whereas the variation in H GW declined with decreasing LD. However, less intuitively, there was no positive correlation between the variation in H M and H GW within inbreeding classes when the local component of H GW was accounted for (i.e. when the part of the chromosome in LD with the markers was excluded). This strongly suggests that within-family HFCs are not caused by general effects. Instead, our results support the idea that HFCs at a known level of inbreeding can be driven by local effects in populations with high to moderate LD. Note however that we define the local component of H GW as the part of the chromosomes in LD with the markers. This implies that when LD is high, the local component will consist of a substantial part of the genome and thus provides a rather 'genome-wide' view. We caution against routinely interpreting positive HFCs as evidence of inbreeding depression and non-significant HFCs as lack thereof, especially when few markers are used. © 2007 Springer Science+Business Media, Inc.
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| 8. |
- Hedmark, Eva, et al.
(författare)
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DNA-based monitoring of two newly founded Scandinavian wolverine populations
- 2007
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Ingår i: Conservation Genetics. - : Springer Science and Business Media LLC. - 1566-0621 .- 1572-9737. ; 8:4, s. 843-852
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Tidskriftsartikel (refereegranskat)abstract
- The wolverine is an endangered carnivore that in northwestern Europe is restricted to the mountain range along the border between Sweden and Norway. The Scandinavian wolverine population experienced a severe decline in numbers due to human persecution during the 20th century, although with legislative protection the population has recently implied that the population slowly has started to recover (current population size estimate of 800 individuals). In the mid 1990s, wolverines appeared in two new and isolated areas east of the mountain range, in the forest landscape close to the Gulf of Bothnia. Using non-invasive, DNA-based monitoring, we show here that these new subpopulations were likely founded by as few as 2 and 2-4 individuals, respectively, and that little, if any, genetic contact with the main population since colonisation has been established. A high degree of genetic similarity among individuals in the two areas indicates inbreeding. We estimate the minimum number of wolverines known to be alive in these areas during the period of 2001-2005 to 5 and 17, respectively, with one subpopulation showing decreasing (currently 2) numbers and the other increasing (10). For the somewhat larger population, we infer a tentative pedigree from relatedness values and parentage tests, which indicates the occurrence of brother-sister matings. This study illustrates the usefulness of non-invasive monitoring in the management of endangered carnivore populations.
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| 9. |
- Hefti-Gautschi, Barbara, et al.
(författare)
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Identification of conservation units in the European Mergus merganser based on nuclear and mitochondrial DNA markers
- 2009
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Ingår i: Conservation Genetics. - : Springer Science and Business Media LLC. - 1566-0621 .- 1572-9737. ; 10:1, s. 87-99
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Tidskriftsartikel (refereegranskat)abstract
- The conservation status of small breeding areas of the Goosander (Mergus merganser merganser) in Central Europe is unclear. Geographic isolation of these areas suggests restricted gene flow to and from large North-European populations. On the other hand, migrating Goosanders from northern Europe join the Central European breeding population for wintering. To evaluate the conservation status of the small breeding areas we assessed the genetic structure of M. merganser populations in Europe by examining two nuclear marker systems (microsatellites and Single Nucleotide Polymorphisms, SNP) and mitochondrial (mtDNA) control region sequence variation for Goosanders in 11 sampling areas representing three of five distinct breeding areas and two subspecies (M. m. merganser and M. m. americanus). Overall population differentiation estimates including both subspecies were high, both based on mtDNA (Phi(ST) = 0.899; P < 0.0001) and nuclear markers (theta(ST) = 0.219; 95% CI 0.088-0.398, SNP and microsatellites combined). Within Europe, mtDNA revealed a strong overall (Phi(ST) = 0.426; P < 0.0001) and significant pairwise population differentiation between almost all comparisons. In contrast, both nuclear marker systems combined revealed only a small overall genetic differentiation (theta(ST) = 0.022; 95% CI 0.003-0.041). The strong genetic differentiation based on female-inherited mtDNA but not on biparentally inherited nuclear markers can be explained by sex-biased dispersal and strong female philopatry. Therefore, small breeding areas in Europe are endangered despite large male-mediated gene-flow, because when these populations decline, only males-but due to strong philopatry not females-can be efficiently supplemented by migration from the large North European populations. We therefore propose to manage the small breeding areas independently and to strengthen conservation efforts for this species in Central Europe.
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| 10. |
- Höglund, Jacob, et al.
(författare)
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Genetic variability in European black grouse (Tetrao tetrix)
- 2007
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Ingår i: Conservation Genetics. - : Springer Science and Business Media LLC. - 1566-0621 .- 1572-9737. ; 8:1, s. 239-243
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Tidskriftsartikel (refereegranskat)abstract
- We studied microsatellite genetic variation in 14 different geographic populations of black grouse (Tetrao tetrix) across the European range. Populations were grouped in three different fragmentation categories: isolated, contiguous and continuous, respectively. Genetic diversity, measured as observed heterozygosity (H O), expected heterozygosity (H E) and allelic richness, were lower in isolated populations as compared to the other two categories that did not differ amongst one another. These results imply that lowered genetic variability in black grouse populations is negatively affected by population isolation. Our results suggest that the connectivity of small and isolated populations in Western Europe should be improved or else these face an increased risk of extinction due to genetic and demographic stochasticity.
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| 11. |
- Knopp, T., et al.
(författare)
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Contrasting levels of variation in neutral and quantitative genetic loci on island populations of moor frogs (Rana arvalis)
- 2007
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Ingår i: Conservation Genetics. - : Springer Science and Business Media LLC. - 1566-0621 .- 1572-9737. ; 8:1, s. 45-56
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Tidskriftsartikel (refereegranskat)abstract
- Reduced levels of genetic variability and a prominent differentiation in both neutral marker genes and phenotypic traits are typical for many island populations as compared to their mainland conspecifics. However, whether genetic diversity in neutral marker genes reflects genetic variability in quantitative traits, and thus, their evolutionary potential, remains typically unclear. Moreover, the phenotypic differentiation on islands could be attributable to phenotypic plasticity, selection or drift; something which seldom has been tested. Using eight polymorphic microsatellite loci and quantitative genetic breeding experiments we conducted a detailed comparison on genetic variability and differentiation between Nordic islands (viz. Gotland, Öland and Læsø) and neighbouring mainland populations of moor frogs (Rana arvalis). As expected, the neutral variation was generally lower in island than in mainland populations. But as opposed to this, higher levels of additive genetic variation (V A) in body size and tibia length were found on the island of Gotland as compared to the mainland population. When comparing the differentiation seen in neutral marker genes (F ST) with the differentiation in genes coding quantitative traits (Q ST) two different evolutionary scenarios were found: while selection might explain a smaller size of moor frogs on Gotland, the differentiation seen in tibia length could be explained by genetic drift. These results highlight the limited utility of microsatellite loci alone in inferring the causes behind an observed phenotypic differentiation, or in predicting the amount of genetic variation in ecologically important quantitative traits.
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| 12. |
- Larsson, Kjell, 1958-, et al.
(författare)
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Population differentiation in the redshank (Tringa totanus) as revealed by mitochondrial DNA and amplified fragment length polymorphism markers
- 2005
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Ingår i: Conservation Genetics. - : Springer Science and Business Media LLC. - 1566-0621 .- 1572-9737. ; 6:3, s. 321-331
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Tidskriftsartikel (refereegranskat)abstract
- The redshank (Tringa totanus) is declining throughout Europe and to implement efficient conservation measures, it is important to obtain information about the population genetic structure. The aim of the present study was two-fold. First, we analysed the genetic variation within and between populations in the Baltic region in southern Scandinavia. Evidence of genetic structure would suggest that different populations might require separate management strategies. Second, in an attempt to study large-scale genetic structure we compared the Baltic populations with redshanks from northern Scandinavia and Iceland. This analysis could reveal insights into phylogeography and long-term population history. DNA samples were collected from six breeding sites in Scandinavia presumed to include two subspecies (totanus and britannica) and a further sample from Iceland (subspecies robusta). Two methods were used to study the population genetic structure. Domain II and III of the mitochondrial control region was analysed by DNA sequencing and nuclear DNA was analysed by screening amplified fragment length polymorphism (AFLP) markers. Mitochondrial DNA showed no variation between individuals in domain II. When analysing an 481 bp fragment of domain III seven haplotypes were found among birds. On the basis of mtDNA sequences, redshanks showed some evidence of a recent expansion from a bottlenecked refugial population. Bayesian analyses of AFLP data revealed a significant genetic differentiation between suggested subspecies but not between populations within the Baltic region. Our results indicate that populations of redshanks in Europe constitute at least three separate management units corresponding to the recognised subspecies.
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| 13. |
- Larsson, Lena C., et al.
(författare)
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Statistical power for detecting genetic divergence–organelle versus nuclear markers
- 2009
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Ingår i: Conservation Genetics. - : Springer Science and Business Media LLC. - 1566-0621 .- 1572-9737. ; 10:5, s. 1255-1264
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Tidskriftsartikel (refereegranskat)abstract
- Statistical power is critical in conservation for detecting genetic differences in space or time from allele frequency data. Organelle and nuclear genetic markers have fundamentally different transmission dynamics; the potential effect of these differences on power to detect divergence have been speculated on but not investigated. We examine, analytically and with computer simulations, the relative performance of organelle and nuclear markers under basic, ideal situations. We conclude that claims of a generally higher resolving power of either marker type are not correct. The ratio R = FST,organelle/FST,nuclear varies between 1 and 4 during differentiation and this greatly affects the power relationship. When nuclear FST is associated with organelle differentiation four times higher, the power of the organelle marker is similar to two nuclear loci with the same allele frequency distribution. With large sample sizes (n C 50) and several populations or many alleles per locus (C5), the power difference may typically be disregarded when nuclear FST[0.05. To correctly interpret observed patterns of genetic differentiation in practical situations, the expected FSTs and the statistical properties (i.e., power analysis) of the genetic markers used should be evaluated, taking the observed allele frequency distributions into consideration.
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| 14. |
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| 15. |
- Ramirez, O., et al.
(författare)
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Genetic assessment of the Iberian wolf Canis lupus signatus captive breeding program
- 2006
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Ingår i: Conservation Genetics. - : Springer Science and Business Media LLC. - 1566-0621 .- 1572-9737. ; 7:6, s. 861-878
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Tidskriftsartikel (refereegranskat)abstract
- The main goal of ex situ conservation programs is to improve the chances of long term survival of natural populations by founding and managing captive colonies that can serve as a source of individuals for future reintroductions or to reinforce existing populations. The degree in which a captive breeding program has captured the genetic diversity existing in the source wild population has seldom been evaluated. In this study we evaluate the genetic diversity in wild and captive populations of the Iberian wolf, Canis lupus signatus, in order to assess how much genetic diversity is being preserved in the ongoing ex situ conservation program for this subspecies. A sample of domestic dogs was also included in the analysis for comparison. Seventy-four wolves and 135 dogs were genotyped at 13 unlinked microsatellite loci. The results show that genetic diversity in Iberian wolves is comparable in magnitude to that of other wild populations of gray wolf. Both the wild and the captive Iberian wolf populations have a similarly high genetic diversity indicating that no substantial loss of diversity has occurred in the captive-breeding program. The effective number of founders of the program was estimated as similar to 16, suggesting that all founders in the studbook pedigree were genetically independent. Our results emphasize also the genetic divergence between wolves and domestic dogs and indicate that our set of 13 microsatellite loci provide a powerful diagnostic test to distinguish wolves, dogs and their hybrids.
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| 16. |
- Ruokonen, Minna, et al.
(författare)
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Using historical captive stocks in conservation. The case of the lesser white-fronted goose
- 2007
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Ingår i: Conservation Genetics. - : Springer Science and Business Media LLC. - 1566-0621 .- 1572-9737. ; 8:1, s. 197-207
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Tidskriftsartikel (refereegranskat)abstract
- Many captive stocks of economically or otherwise valuable species were established before the decline of the wild population. These stocks are potentially valuable sources of genetic variability, but their taxonomic identity and actual value is often uncertain. We studied the genetics of captive stocks of the threatened lesser white-fronted goose Anser erythropus maintained in Sweden and elsewhere in Europe. Analyses of mtDNA and nuclear microsatellite markers revealed that 36% of the individuals had a hybrid ancestry. Because the parental species are closely related it is unlikely that our analyses detected all hybrid individuals in the material. Because no ancestral polymorphism or introgression was observed in samples of wild populations, it is likely that the observed hybridisation has occurred in captivity. As a consequence of founder effect, drift and hybridisation, captive stocks were genetically differentiated from the wild populations of the lesser white-fronted goose. The high level of genetic diversity in the captive stocks is explained at least partially by hybridisation. The present captive stocks of the lesser white-fronted goose are considered unsuitable for further reintroduction, or supplementation: hybridisation has involved three species, the number of hybrids is high, and all the investigated captive stocks are similarly affected. The results highlight the potential shortcomings of using captive-bred individuals in supplementation and reintroduction projects, when the captive stocks have not been pedigreed and bred according to conservation principles.
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| 17. |
- Sagvik, Jörgen, 1972, et al.
(författare)
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Outbreeding depression in the common frog, Rana temporaria
- 2005
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Ingår i: Conservation Genetics. - : Springer Science and Business Media LLC. - 1566-0621 .- 1572-9737. ; 6:2, s. 205-211
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Tidskriftsartikel (refereegranskat)abstract
- Theory suggests that parental relatedness is a continuous variable with a fitness optimum that we heretoforth will refer to as 'optimal outbreeding. In the present paper, we test this proposition from a conservation (translocation) perspective. Amphibians are facing a global decline and many amphibian populations are today small and threatened by extinction. Because genetic differentiation is often high between amphibian populations, they could be particularly sensitive to outbreeding depression, e.g. due to breakdown of locally adapted gene complexes. We tested if outbreeding would reduce fitness in common frogs, Rana temporaria, crossed from a large and an isolated, small population, separated by 130 km, using artificial fertilization. For females from the large population, tadpoles were significantly smaller and more malformed in crosses with males from the small population, than with males from the large population. For the small population, however, no significant paternal genetic effects could be found. The difference in response to outbreeding between populations was accompanied with significant differences in the importance of maternal effects. We conclude that care should be taken when translocating frogs between distantly related populations to avoid outbreeding depression.
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| 18. |
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| 19. |
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| 20. |
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| 21. |
- Semerikov, Vladimir L., et al.
(författare)
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RAPD-derived, PCR-based mitochondrial markers for Larix species and their usefulness in phylogeny
- 2006
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Ingår i: Conservation Genetics. - : Springer Science and Business Media LLC. - 1566-0621 .- 1572-9737. ; 7:4, s. 621-625
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Tidskriftsartikel (refereegranskat)abstract
- Random amplified polymorphic DNA (RAPDs) from plants contains numerous fragments of mitochondrial origin. In the present study, the association between RAPD bands and previously recognized mitochondrial polymorphism in a Larix population was used to identify fragments of mitochondrial origin and to develop PCR-based mitochondrial DNA markers useful to study phylogeny in larches, Larix sp. (Pinaceae).
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| 22. |
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| 23. |
- Sundqvist, Anna-Karin, et al.
(författare)
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Wolf or dog? Genetic identification of predator from saliva collected around bite wounds on prey
- 2008
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Ingår i: Conservation Genetics. - : Springer Science and Business Media LLC. - 1566-0621 .- 1572-9737. ; 9:5, s. 1275-1279
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Tidskriftsartikel (refereegranskat)abstract
- Wolf predation on livestock is a management problem in many areas and is often used to justify control measures against the wolves. However, wolves coexist with dogs across their range, and dogs could be responsible for attacks blamed on wolves. In this study we evaluate the possibility of obtaining sufficient DNA for species identification of the predator from saliva remaining close to bite wounds following a canid attack. Predator DNA of reasonably high quality was successfully extracted from bite wounds on two sheep that had been attacked on a farm and were genotyped using six informative microsatellite markers. A single consensus genotype could be constructed from the bite wounds of both sheep which we compared to genotypes obtained from Scandinavian wolves and dogs. The results clearly showed that the saliva sampled originated from a single dog. This report thus demonstrates the feasibility of predator species identification from bite wounds and also illustrates that it can not be taken for granted that wolves are responsible for canid livestock kills.
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| 24. |
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| 25. |
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