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1.
Nat Ecol Evol ; 8(2): 267-281, 2024 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-38225425

RESUMO

Genetic monitoring of populations currently attracts interest in the context of the Convention on Biological Diversity but needs long-term planning and investments. However, genetic diversity has been largely neglected in biodiversity monitoring, and when addressed, it is treated separately, detached from other conservation issues, such as habitat alteration due to climate change. We report an accounting of efforts to monitor population genetic diversity in Europe (genetic monitoring effort, GME), the evaluation of which can help guide future capacity building and collaboration towards areas most in need of expanded monitoring. Overlaying GME with areas where the ranges of selected species of conservation interest approach current and future climate niche limits helps identify whether GME coincides with anticipated climate change effects on biodiversity. Our analysis suggests that country area, financial resources and conservation policy influence GME, high values of which only partially match species' joint patterns of limits to suitable climatic conditions. Populations at trailing climatic niche margins probably hold genetic diversity that is important for adaptation to changing climate. Our results illuminate the need in Europe for expanded investment in genetic monitoring across climate gradients occupied by focal species, a need arguably greatest in southeastern European countries. This need could be met in part by expanding the European Union's Birds and Habitats Directives to fully address the conservation and monitoring of genetic diversity.


Assuntos
Mudança Climática , Conservação dos Recursos Naturais , Conservação dos Recursos Naturais/métodos , Europa (Continente) , Ecossistema , Variação Genética
2.
Bioscience ; 71(9): 964-976, 2021 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-34475806

RESUMO

Global conservation policy and action have largely neglected protecting and monitoring genetic diversity-one of the three main pillars of biodiversity. Genetic diversity (diversity within species) underlies species' adaptation and survival, ecosystem resilience, and societal innovation. The low priority given to genetic diversity has largely been due to knowledge gaps in key areas, including the importance of genetic diversity and the trends in genetic diversity change; the perceived high expense and low availability and the scattered nature of genetic data; and complicated concepts and information that are inaccessible to policymakers. However, numerous recent advances in knowledge, technology, databases, practice, and capacity have now set the stage for better integration of genetic diversity in policy instruments and conservation efforts. We review these developments and explore how they can support improved consideration of genetic diversity in global conservation policy commitments and enable countries to monitor, report on, and take action to maintain or restore genetic diversity.

3.
Mol Biol Rep ; 47(4): 2975-2984, 2020 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-32236892

RESUMO

Toll-like receptors (TLRs) are transmembrane proteins of the innate immune system, composed of the ectodomain involved in pathogen recognition and the intracellular Toll/interleukin-1 receptor (TIR) domain important for downstream signal transduction. Here, we analyze the genetic variability of TIR nucleotide and amino-acid sequences of the TLR2 gene in 243 brown hares from Europe and the Middle East and tested for the presence of selection signals and spatial structuring. TLR2 TIR domain sequences were PCR amplified and sequenced, while genotyping was performed by phasing. Genetic diversity indices were calculated in DnaSP and Arlequin, while presence of selection signals was tested using MEGA and the Datamonkey web server. The presence of spatial patterns in TIR sequence distribution was tested by spatial Principal Component Analysis (sPCA) in adegenet. A total of 13 haplotypes were revealed with haplotype diversity of 0.424, and nucleotide diversity (π) of 0.00138. Two spatial clusters were revealed: "Anatolia/Middle East" and "Europe". In Anatolia the two most prevalent amino-acid variants, A and B (the latter being the most ancestral) were maintained at similar frequencies; but in Europe a shift in genotype frequencies was observed as well as a higher number of nonsynonymous substitutions giving rise to novel amino-acid protein variants originating from the evolutionarily younger protein variant. Molecular diversity (haplotype and nucleotide diversity) indices were significantly higher in the "Anatolia/Middle East" cluster. A signal of purifying selection was detected acting on the TIR sequences.


Assuntos
Lebres/genética , Receptor 2 Toll-Like/genética , Alelos , Animais , Evolução Biológica , Europa (Continente) , Evolução Molecular , Variação Genética/genética , Genótipo , Haplótipos/genética , Lebres/metabolismo , Oriente Médio , Filogenia , Seleção Genética/genética , Análise de Sequência de DNA/métodos , Receptor 2 Toll-Like/metabolismo , Receptores Toll-Like/genética
4.
PLoS One ; 14(11): e0224902, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31703111

RESUMO

Previous studies in hares and jackrabbits have indicated that positive selection has shaped the genetic diversity of mitochondrial genes involved in oxidative phosphorylation, which may affect cellular energy production and cause regional adaptation to different environmental (climatic) pressures. In the present study, we sequenced the NADH dehydrogenase subunit 6 (MT-ND6) gene of 267 brown hares (L. europaeus) from Europe and Asia Minor and tested for positive selection and adaptations acting on amino acid sequences (protein variants). Molecular diversity indices and spatial clustering were assessed by DnaSP, Network, and Geneland, while the presence of selection signals was tested by codeml in PAML, and by using the Datamonkey Adaptive Evolution web server. The SPSS software was used to run multinomial regression models to test for possible effects of climate parameters on the currently obtained protein variants. Fifty-eight haplotypes were revealed with a haplotype diversity of 0.817, coding for 17 different protein variants. The MT-ND6 phylogeographic pattern as determined by the nucleotide sequences followed the earlier found model based on the neutrally evolving D-loop sequences, and reflected the earlier found phylogeographic Late Pleistocene scenario. Based on several selection tests, only one codon position consistently proved to be under positive selection. It did occur exclusively in the evolutionarily younger hares from Europe and it gave rise to several protein variants from the southeastern and south-central Balkans. The occurrence of several of those variants was significantly favored under certain precipitation conditions, as proved by our multinomial regression models. Possibly, the great altitudinal variation in the Balkans may have lead to bigger changes in precipitation across that region and this may have imposed an evolutionarily novel selective pressure on the protein variants and could have led to regional adaptation.


Assuntos
Genes Mitocondriais , Lebres/classificação , Lebres/genética , NADH Desidrogenase/genética , Filogenia , Filogeografia , Seleção Genética , Alelos , Animais , Variação Genética , Genótipo , Haplótipos , Sequenciamento de Nucleotídeos em Larga Escala , Análise de Sequência de DNA
5.
PLoS One ; 13(7): e0200805, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-30028840

RESUMO

An ongoing study of the genus Merodon Meigen, 1803 in the Republic of South Africa (RSA) has revealed the existence of new species related to M. melanocerus Bezzi, 1915. The M. melanocerus subgroup belongs to the Afrotropical lineage of the M. desuturinus group. Revision of all available material from museums and detailed analyses of newly -collected specimens from our own expeditions to RSA resulted in delimitation of five species: M. capensis Hurkmans sp. n., M. commutabilis Radenkovic et Vujic sp. n., M. drakonis Vujic et Radenkovic sp. n., M. flavocerus Hurkmans sp. n. and M. melanocerus. In addition to classical morphological characters, sequences of the mitochondrial COI gene are provided for four related taxa. Results of molecular phylogenetic analyses supports monophyly of the M. desuturinus group and confirmed delimitation between species. Links between Palaearctic and Afrotropical faunas of this group, as well as possible evolutionary paths, are discussed. Based on phylogenetic analyses, four lineages (putative subgenera) have been recognized within the genus Merodon; besides the three previously established ones, albifrons+desuturinus, aureus (sensu lato) and avidus-nigritarsis, one new lineage named natans is distinguished.


Assuntos
Distribuição Animal , Evolução Biológica , Dípteros/classificação , Genes Mitocondriais , Animais , Teorema de Bayes , Dípteros/genética , Complexo IV da Cadeia de Transporte de Elétrons/metabolismo , Feminino , Geografia , Masculino , Museus , Filogenia , Reprodutibilidade dos Testes , África do Sul , Especificidade da Espécie , Manejo de Espécimes
6.
Int J Legal Med ; 132(2): 405-408, 2018 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-28868569

RESUMO

The analysis of 12 X-STR loci included in the Investigator® Argus X-12 kit was performed on a sample of 325 unrelated persons from Vojvodina Province, Republic of Serbia. No significant differences were observed in the allele frequencies in males and females. Heterozygosity values among the studied loci ranged from 67.62 to 94.28%. All loci in female individuals were consistent with the Hardy-Weinberg equilibrium test. The combined power of discrimination values in male and female individuals was 0.9999999994 and 0.999999999999999, respectively. The combined mean exclusion chance was 0.999998 in deficiency cases, 0.9999999977 in normal trio cases, and 0.9999994 in duo cases. Loci DXS10135 and DXS10101 were found to be most polymorphic. The haplotype diversity was found to be greater than 0.993 for all linkage groups. The exact test for pairwise linkage disequilibrium for the 12 loci in the male samples showed significant linkage disequilibrium for the DXS10103-DXS10101 and DXS10134-DXS10146 pairs of loci. The results from the current study confirmed that the panel of 12 X-STR loci is highly polymorphic and informative and can be implemented as a powerful tool in deficient paternity testing and kinship analysis, as well as a useful complement tool of autosomal short tandem repeats (STRs) in forensic investigation. Population differentiation analyses indicated significant differences in genetic structure between the Serbian population and the geographically and ethno-linguistically distant populations, while genetic homogeneity was present in populations with similar geographic origin.


Assuntos
Cromossomos Humanos X , Genética Populacional , Repetições de Microssatélites , Impressões Digitais de DNA , Feminino , Frequência do Gene , Haplótipos , Humanos , Masculino , Reação em Cadeia da Polimerase , Polimorfismo Genético , Sérvia
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