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1.
Heredity (Edinb) ; 132(1): 54-66, 2024 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-38082151

RESUMO

Climate projections predict major changes in alpine environments by the end of the 21st century. To avoid climate-induced maladaptation and extinction, many animal populations will either need to move to more suitable habitats or adapt in situ to novel conditions. Since populations of a species exhibit genetic variation related to local adaptation, it is important to incorporate this variation into predictive models to help assess the ability of the species to survive climate change. Here, we evaluate how the adaptive genetic variation of a mountain ungulate-the Northern chamois (Rupicapra rupicapra)-could be impacted by future global warming. Based on genotype-environment association analyses of 429 chamois using a ddRAD sequencing approach, we identified genetic variation associated with climatic gradients across the European Alps. We then delineated adaptive genetic units and projected the optimal distribution of these adaptive groups in the future. Our results suggest the presence of local adaptation to climate in Northern chamois with similar genetic adaptive responses in geographically distant but climatically similar populations. Furthermore, our results predict that future climatic changes will modify the Northern chamois adaptive landscape considerably, with various degrees of maladaptation risk.


Assuntos
Rupicapra , Animais , Rupicapra/genética , Ecossistema , Mudança Climática
2.
J Hered ; 105(1): 70-81, 2014.
Artigo em Inglês | MEDLINE | ID: mdl-24154535

RESUMO

The Hermann's tortoise (Testudo hermanni) is an endangered land tortoise distributed in disjoint populations across Mediterranean Europe. We investigated its genetic variation by typing 1 mitochondrial locus and 9 nuclear microsatellites in approximately 300 individuals from 22 localities. Our goal was to understand the relative impact of natural and human-mediated processes in shaping the genetic structure and to identify the genetic priorities for the conservation of this species. We found that 1) all geographic areas are highly differentiated, mainly as a function of their distance but with a clear genetic discontinuity (F st values larger than 0.4) between the Eastern and the Western subspecies; 2) the contact zone between subspecies is located farthest to the west than previously believed, and it probably coincides with the delta of the largest Italian river; 3) extinction events due to climatic conditions in the Upper Palaeolithic and subsequent human-mediated translocations in the Neolithic possibly explain the unexpected similarity among Spain, Sicily, and Corsica. For conservation purposes, the large majority of genetic pools appears native although hybridization among subspecies, related to extensive 20th century trade of tortoises across Europe, is observed in Spain and some Italian samples. Most populations do not seem at immediate risk of low genetic variation, except the French population, which has very low nuclear genetic diversity (heterozygosity = 0.25) and where 50 out of 51 sampled animals shared the same mitochondrial sequence. In general, restocking and reintroduction plans should carefully consider the genetic background of the individuals.


Assuntos
DNA Mitocondrial/isolamento & purificação , Variação Genética , Tartarugas/classificação , Tartarugas/genética , Animais , Conservação dos Recursos Naturais , DNA Mitocondrial/genética , França , Loci Gênicos , Hibridização Genética , Desequilíbrio de Ligação , Repetições de Microssatélites , Filogeografia , Análise de Sequência de DNA
3.
Pathogens ; 12(1)2022 Dec 30.
Artigo em Inglês | MEDLINE | ID: mdl-36678408

RESUMO

The assessment of red fox population density is considered relevant to the surveillance of zoonotic agents vectored by this species. However, density is difficult to estimate reliably, since the ecological plasticity and elusive behavior of this carnivore hinder classic methods of inference. In this study, red fox population density was estimated using a non-invasive molecular spatial capture-recapture (SCR) approach in two study areas: one in a known hotspot of the zoonotic cestode Echinococcus multilocularis, and another naïve to the parasite. Parasitological investigations on collected samples confirmed the presence of the parasite exclusively in the former area; the SCR results indicated a higher fox population density in the control area than in the hotspot, suggesting either that the relationship between fox density and parasite prevalence is not linear and/or the existence of other latent factors supporting the parasitic cycle in the known focus. In addition, fox spotlight count data for the two study areas were used to estimate the index of kilometric abundance (IKA). Although this method is cheaper and less time-consuming than SCR, IKA values were the highest in the areas with the lower molecular SCR density estimates, confirming that IKA should be regarded as a relative index only.

4.
Forensic Sci Int Genet ; 51: 102447, 2021 03.
Artigo em Inglês | MEDLINE | ID: mdl-33401133

RESUMO

The illegal trade has been threatening tortoise populations worldwide for decades. Nowadays, however, DNA typing and forensic genetic approaches allow us to investigate the geographic origin of confiscated animals and to relocate them into the wild, providing that suitable molecular tools and reference data are available. Here we assess the suitability of a small panel of microsatellite markers to investigate patterns of illegal translocations and to assist forensic genetic applications in the endangered Mediterranean land tortoise Testudo hermanni hermanni. Specific allelic ladders were created for each locus and tested on several reference samples. We used the microsatellite panel to (i) increase our understanding of the population genetic structure in wild populations with new data from previously unsampled geographic areas (overall 461 wild individuals from 28 sampling sites); (ii) detect the presence of non-native individuals in wild populations; and (iii) identify the most likely geographic area of origin of 458 confiscated individuals hosted in Italian seizure and recovery centers. Our analysis initially identified six major genetic clusters corresponding to different geographic macro-areas along the Mediterranean range. Long-distance migrants among wild populations, due to translocations, were found and removed from the reference database. Assignment tests allowed us to allocate approximately 70 % of confiscated individuals of unknown origin to one of the six Mediterranean macro-areas. Most of the assigned tortoises belonged to the genetic cluster corresponding to the area where the respective captivity center was located. However, we also found evidence of long-distance origins of confiscated individuals, especially in centers along the Adriatic coast and facing the Balkan regions, a well-known source of illegally traded individuals. Our results clearly show that the microsatellite panel and the reference dataset can play a beneficial role in reintroduction and repatriation projects when confiscated individuals need to be re-assigned to their respective macro-area of origin before release, and can assist future forensic genetic applications in detecting the illegal trade and possession of Testudo hermanni individuals.


Assuntos
Filogeografia , Tartarugas/genética , Animais , Conservação dos Recursos Naturais , Impressões Digitais de DNA , Repetições de Microssatélites
5.
J Hered ; 100(6): 691-708, 2009.
Artigo em Inglês | MEDLINE | ID: mdl-19617524

RESUMO

The chamois is a useful species with which to investigate the combined genetic impact of habitat fragmentation, over hunting, and translocations. Genetic variation within and between chamois (genus Rupicapra) populations was analyzed in 259 individuals from 16 sampling sites located in Italy, Spain, Slovakia, and the Czech Republic. Two mitochondrial DNA markers (control region and cytochrome b) and 11 nuclear microsatellites were typed. The principal results of this study can be summarized as follows: 1) high and significant differentiation between almost all chamois populations is observed even on a microgeographical scale, probably caused by the patchy distribution of this species, sharp geographical barriers to gene flow, and drift effects related to recent bottlenecks; 2) historical translocation events have left a clear genetic signature, including interspecific hybridization in some Alpine localities; 3) the Apennine subspecies of chamois, Rupicapra pyrenaica ornata, shows a high and similar level of divergence (about 1.5 My) from the Pyrenean (Rupicapra pyrenaica pyrenaica) and the Alpine (Rupicapra rupicapra) chamois; therefore, the specific status of these taxa should be revised. These results confirm the potential of population genetic analyses to dissect and interpret complex patterns of diversity in order to define factors important to conservation and management.


Assuntos
Ecossistema , Evolução Molecular , Fluxo Gênico/genética , Variação Genética , Genética Populacional , Filogenia , Rupicapra/genética , Animais , Sequência de Bases , Teorema de Bayes , Biologia Computacional , Conservação dos Recursos Naturais/métodos , DNA Mitocondrial/genética , Demografia , Europa (Continente) , Geografia , Funções Verossimilhança , Repetições de Microssatélites/genética , Modelos Genéticos , Dados de Sequência Molecular , Rupicapra/classificação , Análise de Sequência de DNA , Especificidade da Espécie
6.
PLoS One ; 14(3): e0213515, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-30861028

RESUMO

Information on the population dynamics of a reservoir species have been increasingly adopted to understand and eventually predict the dispersal patterns of infectious diseases throughout an area. Although potentially relevant, to date there are no studies which have investigated the genetic structure of the red fox population in relation to infectious disease dynamics. Therefore, we genetically and spatially characterised the red fox population in the area stretching between the Eastern and Dinaric Alps, which has been affected by both distemper and rabies at different time intervals. Red foxes collected from north-eastern Italy, Austria, Slovenia and Croatia between 2006-2012, were studied using a set of 21 microsatellite markers. We confirmed a weak genetic differentiation within the fox population using Bayesian clustering analyses, and we were able to differentiate the fox population into geographically segregated groups. Our finding might be due to the presence of geographical barriers that have likely influenced the distribution of the fox population, limiting in turn gene flow and spread of infectious diseases. Focusing on the Italian red fox population, we observed interesting variations in the prevalence of both diseases among distinct fox clusters, with the previously identified Italy 1 and Italy 2 rabies as well as distemper viruses preferentially affecting different sub-groups identified in the study. Knowledge of the regional-scale population structure can improve understanding of the epidemiology and spread of diseases. Our study paves the way for an integrated approach for disease control coupling pathogen, host and environmental data to inform targeted control programs in the future.


Assuntos
Cinomose , Raposas/genética , Repetições de Microssatélites , Raiva , Animais , Áustria/epidemiologia , Croácia/epidemiologia , Cinomose/epidemiologia , Cinomose/genética , Cinomose/transmissão , Cães , Feminino , Masculino , Prevalência , Raiva/epidemiologia , Raiva/genética , Raiva/transmissão , Raiva/veterinária , Eslovênia/epidemiologia
7.
PLoS One ; 12(1): e0170507, 2017.
Artigo em Inglês | MEDLINE | ID: mdl-28114306

RESUMO

The rock partridge, Alectoris graeca, is a polytypic species declining in Italy mostly due to anthropogenic causes, including the massive releases of the closely related allochthonous chukar partridge Alectoris chukar which produced the formation of hybrids. Molecular approaches are fundamental for the identification of evolutionary units in the perspective of conservation and management, and to correctly select individuals to be used in restocking campaigns. We analyzed a Cytochrome oxidase I (COI) fragment of contemporary and historical A. graeca and A. chukar samples, using duplicated analyses to confirm results and nuclear DNA microsatellites to exclude possible sample cross-contamination. In two contemporary specimens of A. graeca, collected from an anthropogenic hybrid zone, we found evidence of the presence of mtDNA heteroplasmy possibly associated to paternal leakage and suggesting hybridization with captive-bred exotic A. chukar. These results underline significant limitations in the reliability of mtDNA barcoding-based species identification and could have relevant evolutionary and ecological implications that should be accounted for when interpreting data aimed to support conservation actions.


Assuntos
DNA Mitocondrial/genética , Galliformes/genética , Animais , Hibridização Genética , Filogenia , Especificidade da Espécie
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