Michał J. Dąbrowski


original scientific papers

MIZ PAS affiliation Title: Reliability assessment of null allele detection: Inconsistencies between and within different methods.
Authors: Dąbrowski M.J., Pilot M., Kruczyk M., Żmihorski M., Umer H.M., Gliwicz J.
Source: Molecular Ecology Resources , 14: 361–373.
Published: 2014
Keywords: bottleneck;genotyping errors;heterozygosity;microsatellite loci; Microtus oeconomus ;null alleles
DOI: 10.1111/1755-0998.12177
Microsatellite loci are widely used in population genetic studies, but the presence of null alleles may lead to biased results. Here, we assessed five methods that indirectly detect null alleles and found large inconsistencies among them. Our analysis was based on 20 microsatellite loci genotyped in a natural population of Microtus oeconomus sampled during 8years, together with 1200 simulated populations without null alleles, but experiencing bottlenecks of varying duration and intensity, and 120 simulated populations with known null alleles. In the natural population, 29% of positive results were consistent between the methods in pairwise comparisons, and in the simulated data set, this proportion was 14%. The positive results were also inconsistent between different years in the natural population. In the null-allele-free simulated data set, the number of false positives increased with increased bottleneck intensity and duration. We also found a low concordance in null allele detection between the original simulated populations and their 20% random subsets. In the populations simulated to include null alleles, between 22% and 42% of true null alleles remained undetected, which highlighted that detection errors are not restricted to false positives. None of the evaluated methods clearly outperformed the others when both false-positive and false-negative rates were considered. Accepting only the positive results consistent between at least two methods should considerably reduce the false-positive rate, but this approach may increase the false-negative rate. Our study demonstrates the need for novel null allele detection methods that could be reliably applied to natural populations.

MIZ PAS affiliation Title: Genetic variability of the grey wolf Canis lupus in the Caucasus in comparison with Europe and the Middle East: distinct or intermediary population?
Authors: Pilot M., Dąbrowski M.J., Hayrapetyan V., Yavruyan E.G., Kopaliani N., Tsingarska E., Bujalska B., Kamiński S., Bogdanowicz W.
Source: PLoS ONE, 9(4): e93828.
Published: 2014
Keywords: volves, haplotypes, mitochondrial DNA, population genetics, Europe, haplogroups, Bulgarians, demography
DOI: 10.1371/journal.pone.0093828
Despite continuous historical distribution of the grey wolf (Canis lupus) throughout Eurasia, the species displays considerable morphological differentiation that resulted in delimitation of a number of subspecies. However, these morphological discontinuities are not always consistent with patterns of genetic differentiation. Here we assess genetic distinctiveness of grey wolves from the Caucasus (a region at the border between Europe and West Asia) that have been classified as a distinct subspecies C. l. cubanensis. We analysed their genetic variability based on mtDNA control region, microsatellite loci and genome-wide SNP genotypes (obtained for a subset of the samples), and found similar or higher levels of genetic diversity at all these types of loci as compared with other Eurasian populations. Although we found no evidence for a recent genetic bottleneck, genome-wide linkage disequilibrium patterns suggest a long-term demographic decline in the Caucasian population – a trend consistent with other Eurasian populations. Caucasian wolves share mtDNA haplotypes with both Eastern European and West Asian wolves, suggesting past or ongoing gene flow. Microsatellite data also suggest gene flow between the Caucasus and Eastern Europe. We found evidence for moderate admixture between the Caucasian wolves and domestic dogs, at a level comparable with other Eurasian populations. Taken together, our results show that Caucasian wolves are not genetically isolated from other Eurasian populations, share with them the same demographic trends, and are affected by similar conservation problems.

MIZ PAS affiliation Title: Unregulated hunting and genetic recovery from a severe population decline: the cautionary case of Bulgarian wolves.
Authors: Moura A.E., Tsingarska E., Dąbrowski M.J., Czarnomska S.D., Jędrzejewska B., Pilot M.
Source: Conservation Genetics , 15: 405–417.
Published: 2014
Keywords: Bottleneck Bulgaria Grey wolf Hunting Hybridisation Inbreeding
DOI: 10.1007/s10592-013-0547-y
European wolf (Canis lupus) populations have suffered extensive decline and range contraction due to anthropogenic culling. In Bulgaria, although wolves are still recovering from a severe demographic bottleneck in the 1970s, hunting is allowed with few constraints. A recent increase in hunting pressure has raised concerns regarding long-term viability. We thus carried out a comprehensive conservation genetic analysis using microsatellite and mtDNA markers. Our results showed high heterozygosity levels (0.654, SE 0.031) and weak genetic bottleneck signals, suggesting good recovery since the 1970s decline. However, we found high levels of inbreeding (F IS = 0.113, SE 0.019) and a N e/N ratio lower than expected for an undisturbed wolf population (0.11, 95 % CI 0.08–0.29). We also found evidence for hybridisation and introgression from feral dogs (C. familiaris) in 10 out of 92 wolves (9.8 %). Our results also suggest admixture between wolves and local populations of golden jackals (C. aureus), but less extensive as compared with the admixture with dogs. We detected local population structure that may be explained by fragmentation patterns during the 1970s decline and differences in local ecological characteristics, with more extensive sampling needed to assess further population substructure. We conclude that high levels of inbreeding and hybridisation with other canid species, which likely result from unregulated hunting, may compromise long-term viability of this population despite its current high genetic diversity. The existence of population subdivision warrants an assessment of whether separate management units are needed for different subpopulations. Our study highlights conservation threats for populations with growing numbers but subject to unregulated hunting.

MIZ PAS affiliation Title: Cytochrome b gene (cytb) sequence diversity in a Microtus oeconomus population from Bialowieza Primeval Forest
Authors: Dąbrowski M.J., Pomorski J. J., Gliwicz J.
Source: Acta Theriologica, 58, s. 119-126
Published: 2013

MIZ PAS affiliation Title: Temporally stable genetic variability and dynamic kinship structure in a fluctuating population of the root vole Microtus oeconomus
Authors: Pilot M., Dąbrowski. M.J Jancewicz E., Schtickzelle N., Gliwicz J.
Source: Molecular Ecology, 19, s. 2800-2812
Published: 2010

MIZ PAS affiliation Title: Ecological factors affecting the dial activity of voles in a multi-species community
Authors: Gliwicz J., Dąbrowski M. J.
Source: Annales Zoologici Fennici, 45 (4), s. 242-247
Published: 2008