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A sample of Betula nana from the Linie reserve near Dąbrowa Chełmińska, have been fingerprinted using random amplified polymorphic DNA (RAPD). The high level of genetic variation was detected. All individuals had unique genotypes, supporting the generally high resolving power of RAPD’s. For the conservation strategy, information about the distribution of the genetic variation within and among populations plays very important role. Thus, extensive study in other populations of dwarf birch is needed.
Using a root vole Microtus oeconomus (Pallas, 1776) population in NE Poland we applied 31 microsatellite markers previously developed for root voles and closely related species, with the aim to improve the population genetic tools in this species. Here we present 16 polymorphic microsatellite markers grouped into four sets suitable for simultaneous amplification and genetically sex identification in M. oeconomus. The number of alleles per locus in 227 individuals varied from 7 to 26 with a low frequency of null alleles, expected heterozygosity ranged from 0.758 to 0.927, and observed heterozygosity from 0.722 to 0.947. Two loci showed significant deviation from Hardy-Weinberg equilibrium (p<0.05) and all loci showed independent inheritance. We expect these markers to be useful for studies of genetic population structure and kinship of M. oeconomus populations.
Laboratories worldwide are contributing to a large and growing database for different populations. This study provides a 10 STR database for a population sample of Polish Tatars living in the area of Podlasie for the use as a highly discriminatory system of genetic markers in the forensic community. The genotype frequency distributions showed no deviations from the Hardy-Weinberg equilibrium (HWE) except for D3S1358, FGA, D18S51 and D16S539, based on the Fisher Exact Test. Significant differences between the Polish Tatars and the native population of Podlasie were found in loci D3S1358, FGA, D2S1338, D21S11 and D19S433. The combined values of the Matching Probability and of the Power of Exclusion are 1 in 2.83 × 10⁻¹² and 0.998, respectively.
Biochemical-genetic variation was studied in springbok Antidorcas m. marsupialis (Zimmermann, 1780) from a large (N > 2000) "wild" population (n = 24) and a small (30 > N > 20) isolated farm population (n = 10) using electrophoretic allozyme analysis. Springbok showed polymorphisms at eight out of 46 loci. The springbok from the large population had a higher proportion of polymorphic loci (P = 15.6%) than those from the small population (P = 8.9%). Average heterozygosity (H = 5.1% and H = 4.1%, respectively) was similar for the two populations. This unexpected result is an artefact of the method for calculating H. H:P ratios are lower for the large population than the small one. The distribution of genotypes differed significantly from Hardy-Weinberg equilibrium for two loci. These were found to have a preponderance of homozygotes. This could not be explained by population fragmentation. The levels of polymorphism and heterozygosity are high compared to results from other African bovids.
Genetic variability of three sympatric crucian carp ( Carassius carassius ) populations from NW Poland was studied within a research project aimed at assessing the utility of those populations for stocking in inland waters. DNA samples were collected from 65 individuals. Restriction analysis was performed using 4 enzymes (HaeIII, HinfI, FspBI, TasI) of known restriction sites. The restriction pro files obtained were classified as belonging to a single haplotype (H-1). Selected DNA products were sequenced; the subsequent comparison made it possible to detect the presence of substi- tutions in the genome fragment analysed.
The genetic diversity of two Aconitum species endemic to the Carpathian Mountains and Sudetes was studied. A reticulate evolution between them was earlier postulated as an effect of secondary contact. The genetic diversity at the individual and taxonomic levels was examined across the entire geographical ranges of the taxa in 11 populations based on 247 AFLP markers found in 112 individuals in the Sudetes and Western Carpathians. The overall genetic differentiation was greater within the Sudetic A. plicatum (Fst = 0.139, P < 0.001) than within the Carpathian A. firmum (Fst = 0.062, P < 0.001), presumably due to the long-lasting geographic isolation between the Giant Mts and Praděd (Sudetes) populations of the species. Interestingly, relatively distant and presently isolated populations of A. plicatum and A. f. subsp. maninense share a part of their genomes. It could be an effect of their common evolutionary history, including past and present reticulations. The introgression among infraspecific taxa of Aconitum is common, probably as a result of seed dispersal within a distance of ca. 20 km (Mantel's r = 0.36, P = 0.01). Aconitum f. subsp. maninense had the highest genetic diversity indices: Nei's h and rarefied FAr, and divergence index DW (P < 0.05), pointing to its presumably ancient age and long-term isolation.
Restocking and stock enhancement programs are now recognized as an important tool for the management of fishery resources. It is important, however, to have an adequate knowledge on the genetic population structure of both the released stock and the wild population before carrying out such programs. In this study, random amplified polymorphic DNA (RAPD) markers were applied to assess genetic diversity and population structure of wild and hatchery populations of the white seabream Diplodus sargus and the common two-banded seabream D. vulgaris (Sparidae). The estimated values for intrapopulation genetic variation, measured using the percentage of polymorphic loci (%P), Shannon index (H’), and Nei’s gene diversity (h), showed high values for all populations. The percentage of genetic variation within D. sargus and D. vulgaris populations, based on coefficient of gene differentiation, reached 82.5% and 90% of the total genetic variation, respectively. An undeniable decrease in genetic variation was found in both hatchery populations, particularly in D. sargus, compared to the wild ones. However, the high values of variation within all populations and the low levels of genetic variation among populations did not indicate inbreeding or depression effects, thus indicating a fairly proper hatchery management. Nevertheless, the results of this study highlight the importance of monitoring the genetic variation of hatchery populations, particularly those to be used in restocking programs. The creation of a genetic baseline database will contribute to a more efficient conservation management and to the design of genetically sustainable restocking programs.
Urbanised areas are capable of exerting a strong impact on the distribution of genetic diversity within populations of animals. Urban invertebrate species are currently either relicts from pre-urban ecosystems, or have immigrated during or following urbanisation. We analysed 10 microsatellite loci in 196 specimens of the harlequin ladybird (Harmonia axyridis), an invasive species in Poland sampled in three of the country’s cities. Of Asiatic origin, this ladybird has been spreading through other continents, including Europe. Results showed that the Polish cities are being invaded by harlequin ladybirds that are uniform in terms of their genetic pool, with no significant genetic differentiation present between the urban populations investigated. Rapid spread and what are probably the large numbers of individuals colonising new areas allow this species to maintain high genetic diversity and avoid bottleneck effects. However, we suggest that urban populations differ in terms of genetic diversity. The highest genetic diversity characterises the most recently invaded area of Olsztyn in the north of Poland. Genetic data further suggest that this population could be still in an expansion phase. The earliest colonising population in Wrocław exhibits signs of a Wahlund effect, suggesting that gene flow among local groups within this urban area could be disturbed or impaired. We conclude that, in the case of an urban population of the harlequin ladybird, successful colonisation is followed by the onset of a decline in genetic diversity, with isolation between local sampling sites appearing. Further studies are required, however, if this process is to be elucidated.
Garlic virus A (GarV-A), Garlic virus B (GarV-B), Garlic virus C (GarV-C) and Garlic virus X (GarV-X) are members of the genus Allexivirus in the family Alphaflexiviridae. In this study, we collected 10, 30, 10 and 14 isolates of GarV-A, GarV-B, GarV-C and GarV-X, respectively, from different parts of Poland. All sequences of coat protein (CP) and nucleic-acid binding protein (NABP) regions of Allexivirus isolates available in GenBank were also included in this study. The nucleotide and amino acid sequences identities within each population differed substantially depending on the region of the genome and virus species. The results of selection pressure analysis showed that populations of each Allexivirus underwent negative selection, but the extent of the negative selection varied. It was also concluded that the GarV-A and GarV-C populations underwent a decrease in population size or balancing selection, while the GarV-B and GarV-X populations underwent an increase in population size. It was concluded that both populations of GarV-X evolved independently in each respective area, in contrast to populations of GarV-A, GarV-B and GarV-C.
The North American spiny-cheek crayfish, Orconectes limosus (Cambaridae), endangered in its native range, is a widespread invasive species in European waters and conservationally important carrier of crayfish plague. However, its population structure is poorly known, and no informative genetic markers for the species are available. We tested cross-species transfer of microsatellite loci to spiny-cheek crayfish from 5 other crayfish species. Variability of 10 successfully amplifying loci derived from 4 species was then tested in 60 individuals of O. limosus originating from 3 natural populations: the river Danube at Bogyiszló in Hungary, a pond in Starý Klíčov, and the brook Černovický, both in the Czech Republic. The allele number within the populations ranged from 4 to 10 alleles per locus, while heterozygosity levels varied from 0.650 to 0.900 for Ho and from 0.660 to 0.890 for He. No linkage disequilibrium and no null alleles were detected. The selected markers are useful for assessing population structure, intraspecific variation, and paternity studies in spiny-cheek crayfish.
Bats use various roost types with a wide spectrum of ecological features. The greater mouse-eared bat Myotis myotis (Borkhausen, 1797), creates nurseries in attics and caves in Central Europe. The stable low temperature and high humidity cave microclimate contrasts that of attics, which may alter species adaptations and life strategies. We analysed population characteristics (composition, body condition, parasite load, and immune response) and genetic relatedness of two proximal M. myotis populations. Age, sexual and parasite species composition were similar between the cave and attic sites. However, a significantly higher parasite load and body condition was detected in the post-partum females and juveniles of the cave colony (n = 263 bats from the cave, 231 from the attic), with the cave colony females having a significantly stronger immune response (n = 2 caves and 2 attics, 20 females per site). There was no evidence for genetic divergence between cave and attic populations (n = 3 caves and 3 attics, 24 females per site), indicating that different population characteristics are not genetically based and that M. myotis is an example of a species with rather unique phenotypic plasticity.
The present study investigates the genetic structure of 12 roe deerCapreolus capreolus Linnaeus, 1758 population samples from Serbia, by screening a total of 334 individuals. We examined whether genetic differentiation exists in local populations in Serbia, and addressed the question whether management policies may affect genetic structure. The populations were analysed by multilocus protein electrophoresis, with 33 protein loci examined. Screening of 20 enzymes and one group of general proteins revealed polymorphism at the following 12 loci: Sdh, Mdh-1, Me-1, Idh-2, 6-Pgd-1,αGpd, Ak, Pgm-1, Pgm-2, Ca, Mpi andGpi. Among samples, the proportion of polymorphic loci varied between 3–15.2% (mean 11.9%), while the average gene diversity was in the range of 1.1–4.2%. The overall genetic differentiation was low (θ = 0.03). The comparison of two regional population groups (northern-southern, separated by the Danube River) showed an absence of genetic differentiation between regions. Gene flow was estimated at 8.96 migrants per generation, and was higher in the lowland than in the highland group. Three loci (Ca, 6-Pgd andGpd-1) showed clinal variation along a geographical gradient. Additional five alleles of four loci (Ak, Pgm-1, Gpi, 6-Pgd) showed significant spatial autocorrelation. Genetic distances were small (D = 0–0.004). Northern and southern populations clustered separately. For at least three populations game management practices provide evidence for outlying genetic parameters. The observed heterogeneity in the inbreeding level was deemed more under the influence of non-random mating strengthened by game management, than by overall selective pressure.
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