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1.
Ecol Evol ; 14(4): e11194, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38571789

RESUMO

Hybridization in antelope species has been widely reported in South African national parks and provincial reserves as well as on private land due to anthropogenic effects. In a closed management setting, hybridization may occur due to the crossbreeding of closely related species with unequal sex ratios, resulting in either sterile or fertile offspring. In this study, we used molecular techniques to evaluate the risk of anthropogenic hybridization between blesbok (Damaliscus pygargus phillipsi) and red hartebeest (Alcelaphus buselaphus caama) in an isolated group that purposely included the two species with unequal sex ratios (one red hartebeest male and 19 male and female blesbok). Genetic analysis based on microsatellites confirmed the presence of seven hybrid individuals. Mitochondrial analysis verified that hybridization occurred between blesbok females and the red hartebeest male. STRUCTURE and NEWHYBRIDS classified the hybrids as F1. It is suspected that the hybrid individuals were sterile as the males had undeveloped testes and only F1 hybrids were detected. Thus, the risk of hybridization between these two species may be limited in the wild. In captive settings, genetic monitoring should be included in management plans for blesbok and red hartebeest to ensure that the long-term consequences of wasted reproductive effort are limited.

2.
Ecol Evol ; 14(3): e10962, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-38450323

RESUMO

Bontebok (Damaliscus pygargus pygargus) and blesbok (D. p. phillipsi) are classified as separate sub-species. The blesbok has a widespread distribution throughout South Africa and is listed as least concern by the International Union for Conservation of Nature (IUCN) Red List of Threatened Species. Bontebok on the other hand is endemic within the Cape Floristic Region of the Western Cape in South Africa and has been listed as near-threatened species on the IUCN Red List of Threatened Species. Bontebok populations experienced a severe bottleneck and were brought back from the brink of extinction in the 1830s. Currently, the subspecies is threatened by hybridisation with blesbok resulting in fertile offspring. To date, molecular investigations using neutral markers have determined that genetic diversity in pure South African bontebok was significantly lower than in pure blesbok. Here, we investigated genetic diversity in bontebok, blesbok and hybrid individuals using microsatellites and an adaptive marker (toll-like receptor two (TLR2)). The study of single nucleotide polymorphisms (SNPs) revealed five mutations in TLR2 in different individuals and subspecies of D. pygargus. This included three non-synonymous and two synonymous mutations. The three amino acid substitution mutations were predicted to have no effect on protein function. Two of the five mutations, one of which resulted in an amino acid substitution, were not present in bontebok. The other three mutations were present to varying frequencies in the three groups. We confirm low adaptive and neutral diversity in bontebok. These mutations provide insights into the genetic diversity and relationships among the two sub-species of D. pygargus and may have implications for their conservation and management.

3.
Mol Ecol Resour ; 24(4): e13940, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-38390700

RESUMO

Age is a key demographic in conservation where age classes show differences in important population metrics such as morbidity and mortality. Several traits, including reproductive potential, also show senescence with ageing. Thus, the ability to estimate age of individuals in a population is critical in understanding the current structure as well as their future fitness. Many methods exist to determine age in wildlife, with most using morphological features that show inherent variability with age. These methods require significant expertise and become less accurate in adult age classes, often the most critical groups to model. Molecular methods have been applied to measuring key population attributes, and more recently epigenetic attributes such as methylation have been explored as biomarkers for age. There are, however, several factors such as permits, sample sovereignty, and costs that may preclude the use of extant methods in a conservation context. This study explored the utility of measuring age-related changes in methylation in candidate genes using mass array technology. Novel methods are described for using gene orthologues to identify and assay regions for differential methylation. To illustrate the potential application, African cheetah was used as a case study. Correlation analyses identified six methylation sites with an age relationship, used to develop a model with sufficient predictive power for most conservation contexts. This model was more accurate than previous attempts using PCR and performed similarly to candidate gene studies in other mammal species. Mass array presents an accurate and cost-effective method for age estimation in wildlife of conservation concern.


Assuntos
Acinonyx , Humanos , Animais , Acinonyx/genética , Animais Selvagens/genética , Sequência de Bases , Metilação
4.
Sci Rep ; 14(1): 3756, 2024 02 14.
Artigo em Inglês | MEDLINE | ID: mdl-38355905

RESUMO

The anthropogenic impact on wildlife is ever increasing. With shrinking habitats, wild populations are being pushed to co-exist in proximity to humans leading to an increased threat of infectious diseases. Therefore, understanding the immune system of a species is key to assess its resilience in a changing environment. The innate immune system (IIS) is the body's first line of defense against pathogens. High variability in IIS genes, like toll-like receptor (TLR) genes, appears to be associated with resistance to infectious diseases. However, few studies have investigated diversity in TLR genes in vulnerable species for conservation. Large predators are threatened globally including leopards and cheetahs, both listed as 'vulnerable' by IUCN. To examine IIS diversity in these sympatric species, we used next-generation-sequencing to compare selected TLR genes in African leopards and cheetahs. Despite differences, both species show some TLR haplotype similarity. Historic cheetahs from all subspecies exhibit greater genetic diversity than modern Southern African cheetahs. The diversity in investigated TLR genes is lower in modern Southern African cheetahs than in African leopards. Compared to historic cheetah data and other subspecies, a more recent population decline might explain the observed genetic impoverishment of TLR genes in modern Southern African cheetahs. However, this may not yet impact the health of this cheetah subspecies.


Assuntos
Acinonyx , Doenças Transmissíveis , Panthera , Humanos , Animais , Acinonyx/genética , Panthera/genética , Animais Selvagens/genética , Ecossistema
5.
Sci Data ; 10(1): 787, 2023 11 09.
Artigo em Inglês | MEDLINE | ID: mdl-37945571

RESUMO

Birds in seasonal habitats rely on intricate strategies for optimal timing of migrations. This is governed by environmental cues, including photoperiod. Genetic factors affecting intrinsic timekeeping mechanisms, such as circadian clock genes, have been explored, yielding inconsistent findings with potential lineage-dependency. To clarify this evidence, a systematic review and phylogenetic reanalysis was done. This descriptor outlines the methodology for sourcing, screening, and processing relevant literature and data. PRISMA guidelines were followed, ultimately including 66 studies, with 34 focusing on candidate genes at the genotype-phenotype interface. Studies were clustered using bibliographic coupling and citation network analysis, alongside scientometric analyses by publication year and location. Data was retrieved for allele data from databases, article supplements, and direct author communications. The dataset, version 1.0.2, encompasses data from 52 species, with 46 species for the Clock gene and 43 for the Adcyap1 gene. This dataset, featuring data from over 8000 birds, constitutes the most extensive cross-species collection for these candidate genes, used in studies investigating gene polymorphisms and seasonal bird migration.


Assuntos
Migração Animal , Proteínas Aviárias , Aves , Alelos , Ritmo Circadiano/genética , Fotoperíodo , Filogenia , Polimorfismo Genético , Revisões Sistemáticas como Assunto , Animais , Proteínas Aviárias/genética , Migração Animal/fisiologia
6.
Data Brief ; 51: 109615, 2023 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-37822884

RESUMO

The dataset comprises a comprehensive systematic review and meta-analysis exploring the utility of biological clocks as age estimation markers in the context of animal ecology. The systematic review adhered to PRISMA guidelines and employed optimized Boolean search strings to retrieve relevant studies from Scopus and Dimensions databases. A total of 78 methylation studies and 108 telomere studies were included after rigorous screening. Effect sizes were computed, and statistical transformations were applied when necessary, ensuring compatibility for meta-analysis. Data from these studies were meticulously collected, encompassing statistical measures, study attributes, and additional biological information. The dataset comprises several folders, carefully organized to facilitate access and understanding. It contains raw and processed data used in the systematic review and meta-analysis, including Boolean search strings, database search results, citation network analysis data, PRISMA statements, extracted study data, and input data for meta-analysis. Each folder's contents are described in detail, ensuring clarity and reusability. This dataset aggregates primary research studies spanning diverse ecosystems and taxa, providing a valuable resource for researchers, biodiversity managers and policymakers. This dataset offers a wealth of information and analysis potential for researchers studying age estimation markers in animal ecology, serving as a robust foundation for future investigations and reviews in this evolving field.

7.
Biol Rev Camb Philos Soc ; 98(6): 1972-2011, 2023 12.
Artigo em Inglês | MEDLINE | ID: mdl-37356823

RESUMO

Various biological attributes associated with individual fitness in animals change predictably over the lifespan of an organism. Therefore, the study of animal ecology and the work of conservationists frequently relies upon the ability to assign animals to functionally relevant age classes to model population fitness. Several approaches have been applied to determining individual age and, while these methods have proved useful, they are not without limitations and often lack standardisation or are only applicable to specific species. For these reasons, scientists have explored the potential use of biological clocks towards creating a universal age-determination method. Two biological clocks, tooth layer annulation and otolith layering have found universal appeal. Both methods are highly invasive and most appropriate for post-mortem age-at-death estimation. More recently, attributes of cellular ageing previously explored in humans have been adapted to studying ageing in animals for the use of less-invasive molecular methods for determining age. Here, we review two such methods, assessment of methylation and telomere length, describing (i) what they are, (ii) how they change with age, and providing (iii) a summary and meta-analysis of studies that have explored their utility in animal age determination. We found that both attributes have been studied across multiple vertebrate classes, however, telomere studies were used before methylation studies and telomere length has been modelled in nearly twice as many studies. Telomere length studies included in the review often related changes to stress responses and illustrated that telomere length is sensitive to environmental and social stressors and, in the absence of repair mechanisms such as telomerase or alternative lengthening modes, lacks the ability to recover. Methylation studies, however, while also detecting sensitivity to stressors and toxins, illustrated the ability to recover from such stresses after a period of accelerated ageing, likely due to constitutive expression or reactivation of repair enzymes such as DNA methyl transferases. We also found that both studied attributes have parentally heritable features, but the mode of inheritance differs among taxa and may relate to heterogamy. Our meta-analysis included more than 40 species in common for methylation and telomere length, although both analyses included at least 60 age-estimation models. We found that methylation outperforms telomere length in terms of predictive power evidenced from effect sizes (more than double that observed for telomeres) and smaller prediction intervals. Both methods produced age correlation models using similar sample sizes and were able to classify individuals into young, middle, or old age classes with high accuracy. Our review and meta-analysis illustrate that both methods are well suited to studying age in animals and do not suffer significantly from variation due to differences in the lifespan of the species, genome size, karyotype, or tissue type but rather that quantitative method, patterns of inheritance, and environmental factors should be the main considerations. Thus, provided that complex factors affecting the measured trait can be accounted for, both methylation and telomere length are promising targets to develop as biomarkers for age determination in animals.


Assuntos
Envelhecimento , Relógios Biológicos , Humanos , Animais , Ecologia , Cariotipagem
8.
J Mol Evol ; 91(4): 502-513, 2023 08.
Artigo em Inglês | MEDLINE | ID: mdl-37079046

RESUMO

Evolutionary processes happen gradually over time and are, thus, considered time dependent. In addition, several evolutionary processes are either adaptations to local habitats or changing habitats, otherwise restricted thereby. Since evolutionary processes driving speciation take place within the landscape of environmental and temporal bounds, several published studies have aimed at providing accurate, fossil-calibrated, estimates of the divergence times of both extant and extinct species. Correct calibration is critical towards attributing evolutionary adaptations and speciation both to the time and paleogeography that contributed to it. Data from more than 4000 studies and nearly 1,50,000 species are available from a central TimeTree resource and provide opportunities of retrieving divergence times, evolutionary timelines, and time trees in various formats for most vertebrates. These data greatly enhance the ability of researchers to investigate evolution. However, there is limited functionality when studying lists of species that require batch retrieval. To overcome this, a PYTHON package termed Python-Automated Retrieval of TimeTree data (PAReTT) was created to facilitate a biologist-friendly interaction with the TimeTree resource. Here, we illustrate the use of the package through three examples that includes the use of timeline data, time tree data, and divergence time data. Furthermore, PAReTT was previously used in a meta-analysis of candidate genes to illustrate the relationship between divergence times and candidate genes of migration. The PAReTT package is available for download from GitHub or as a pre-compiled Windows executable, with extensive documentation on the package available on GitHub wiki pages regarding dependencies, installation, and implementation of the various functions.


Assuntos
Fósseis , Animais , Filogenia
9.
Biol Rev Camb Philos Soc ; 98(4): 1051-1080, 2023 08.
Artigo em Inglês | MEDLINE | ID: mdl-36879518

RESUMO

Timing is a crucial aspect for survival and reproduction in seasonal environments leading to carefully scheduled annual programs of migration in many species. But what are the exact mechanisms through which birds (class: Aves) can keep track of time, anticipate seasonal changes, and adapt their behaviour? One proposed mechanism regulating annual behaviour is the circadian clock, controlled by a highly conserved set of genes, collectively called 'clock genes' which are well established in controlling the daily rhythmicity of physiology and behaviour. Due to diverse migration patterns observed within and among species, in a seemingly endogenously programmed manner, the field of migration genetics has sought and tested several candidate genes within the clock circuitry that may underlie the observed differences in breeding and migration behaviour. Among others, length polymorphisms within genes such as Clock and Adcyap1 have been hypothesised to play a putative role, although association and fitness studies in various species have yielded mixed results. To contextualise the existing body of data, here we conducted a systematic review of all published studies relating polymorphisms in clock genes to seasonality in a phylogenetically and taxonomically informed manner. This was complemented by a standardised comparative re-analysis of candidate gene polymorphisms of 76 bird species, of which 58 are migrants and 18 are residents, along with population genetics analyses for 40 species with available allele data. We tested genetic diversity estimates, used Mantel tests for spatial genetic analyses, and evaluated relationships between candidate gene allele length and population averages for geographic range (breeding- and non-breeding latitude), migration distance, timing of migration, taxonomic relationships, and divergence times. Our combined analysis provided evidence (i) of a putative association between Clock gene variation and autumn migration as well as a putative association between Adcyap1 gene variation and spring migration in migratory species; (ii) that these candidate genes are not diagnostic markers to distinguish migratory from sedentary birds; and (iii) of correlated variability in both genes with divergence time, potentially reflecting ancestrally inherited genotypes rather than contemporary changes driven by selection. These findings highlight a tentative association between these candidate genes and migration attributes as well as genetic constraints on evolutionary adaptation.


Assuntos
Migração Animal , Aves , Animais , Migração Animal/fisiologia , Aves/genética , Polimorfismo Genético , Genótipo , Evolução Biológica , Estações do Ano
10.
Mol Ecol ; 31(16): 4208-4223, 2022 08.
Artigo em Inglês | MEDLINE | ID: mdl-35748392

RESUMO

We live in a world characterized by biodiversity loss and global environmental change. The extinction of large carnivores can have ramifying effects on ecosystems like an uncontrolled increase in wild herbivores, which in turn can have knock-on impacts on vegetation regeneration and communities. Cheetahs (Acinonyx jubatus) serve important ecosystem functions as apex predators; yet, they are quickly heading towards an uncertain future. Threatened by habitat loss, human-wildlife conflict and illegal trafficking, there are only approximately 7100 individuals remaining in nature. We present the most comprehensive genome-wide analysis of cheetah phylogeography and conservation genomics to date, assembling samples from nearly the entire current and past species' range. We show that their phylogeography is more complex than previously thought, and that East African cheetahs (A. j. raineyi) are genetically distinct from Southern African individuals (A. j. jubatus), warranting their recognition as a distinct subspecies. We found strong genetic differentiation between all classically recognized subspecies, thus refuting earlier findings that cheetahs show only little differentiation. The strongest differentiation was observed between the Asiatic and all the African subspecies. We detected high inbreeding in the Critically Endangered Iranian (A. j. venaticus) and North-western (A. j. hecki) subspecies, and show that overall cheetahs, along with snow leopards, have the lowest genome-wide heterozygosity of all the big cats. This further emphasizes the cheetah's perilous conservation status. Our results provide novel and important information on cheetah phylogeography that can support evidence-based conservation policy decisions to help protect this species. This is especially relevant in light of ongoing and proposed translocations across subspecies boundaries, and the increasing threats of illegal trafficking.


Assuntos
Acinonyx , Acinonyx/genética , Animais , Ecossistema , Genoma , Genômica , Humanos , Irã (Geográfico)
11.
Animals (Basel) ; 12(3)2022 Feb 08.
Artigo em Inglês | MEDLINE | ID: mdl-35158718

RESUMO

Polyphasic skeletal muscle degeneration, necrosis and mineralization of skeletal muscle was diagnosed in eight juvenile free-ranging lions (Panthera leo), from five different litters in the Greater Kruger National Park area that were unable to walk properly. A detailed investigation was not possible in free-ranging lions, so the cause could not be determined. The cases resembled hypokalemic polymyopathy in domestic cats with muscle weakness. A candidate-gene approach previously identified a nonsense mutation in the gene coding for the enzyme lysine-deficient 4 protein kinase (WNK4) associated with the disease in Burmese and Tonkinese cats. In this study, we sequenced all 19 exons of the gene in one case, and two control samples, to identify possible mutations that may be associated with polymyopathy in free-ranging lions. Here, no mutations were detected in any of the exons sequenced. Our findings indicate that the WNK4 gene is not a major contributor to the condition in these lions. Further studies into the pathogenesis of this condition are needed to inform conservation policies for this vulnerable, iconic African species.

12.
Primates ; 63(3): 245-260, 2022 May.
Artigo em Inglês | MEDLINE | ID: mdl-35226214

RESUMO

Forests affected by fragmentation are at risk of losing their primate populations over the long term. The impact of fragmentation on primate populations has been studied in several places in Africa, Asia and South America; however, there has been no discernible pattern of how primates react to forest disturbance and fragmentation. In fragmented habitats, the local extinction probability of a species increases due to a decrease in patch area and an increase in genetic isolation. Here we used microsatellite markers and mitochondrial DNA sequences to investigate how habitat fragmentation impacts on the genetic diversity and structure of a samango monkey population inhabiting forest patches in the Soutpansberg mountain range of northern South Africa. We sampled four local populations across the length of the mountain range and an additional outlying population from the Great Escarpment to the south. Our results indicate that local populations along the mountain range were historically more connected and less distinct than at present. In more recent times, a lack of contemporary gene flow is leading to a more pronounced genetic structure, causing population subdivision across the mountain and likely isolating the Soutpansberg population from the escarpment population to the south. Based on our results, we suggest that natural and anthropogenic fragmentation are driving population genetic differentiation, and that the matrix surrounding forests and their suitability for samango monkey utilisation play a role at the local scale. The degree of genetic isolation found for samango monkey populations in our study raises concerns about the long-term viability of populations across the mountain range.


Assuntos
Cercopithecus , Ecossistema , Animais , Cercopithecus/genética , Florestas , Variação Genética , Genética Populacional , Repetições de Microssatélites , Primatas , África do Sul
13.
Nature ; 599(7884): 209-210, 2021 11.
Artigo em Inglês | MEDLINE | ID: mdl-34667298
14.
PLoS One ; 16(4): e0249306, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-33798210

RESUMO

From 2008 to 2018, South Africa permitted the export of captive-bred African lion (Panthera leo) skeletons to Southeast Asia under CITES Appendix II. Legal exports rose from approximately 50 individuals in 2008 to a maximum of 1,771 skeletons in 2016, and has led to ongoing concerns over possible laundering of non-lion, multiple-source and wild-sourced bones. South Africa is required under its obligations to CITES to employ mechanisms for monitoring and reporting trade, and to limit the potential for illegal trade and laundering of lion and other large felid bones. Monitoring tools for legal trade are critical to compliance with CITES. Here we evaluate the CITES-compliance procedure implemented by South Africa for export of lion bones and identify six essential general points for consideration in the implementation of animal export quota compliance protocols. We provide specific insight into the South African lion bone export monitoring system through: i) outlining the protocols followed; ii) assessing the utility of cranial morphology to identify species; iii) evaluating skeleton consignment weight as a monitoring tool; and iv) presenting molecular (DNA) species assignment and pairwise-comparative sample matching of individuals. We describe irregularities and illicit behaviour detected in the 2017 and 2018 lion bone quotas. Notably, we report that the compliance procedure successfully identified and prevented the attempted laundering of a tiger (P. tigris) skeleton in 2018. We emphasise the utility of mixed-method protocols for the monitoring of compliance in CITES Appendix II export quota systems.


Assuntos
Conservação dos Recursos Naturais/economia , Espécies em Perigo de Extinção/economia , Fidelidade a Diretrizes/estatística & dados numéricos , Leões , Crânio , Animais , Cruzamento , África do Sul
15.
Primates ; 62(4): 667-675, 2021 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-33909155

RESUMO

The habitats of Galago moholi are suspected to be largely fragmented, while the species is thought to be expanding further into the southernmost fringe of its range, as well as into human settlements. To date, no intraspecific molecular genetic studies have been published on G. moholi. Here we estimate the genetic diversity and connectivity of populations of G. moholi using two mitochondrial gene regions, the cytochrome C oxidase subunit I gene (COI) and the displacement loop of the control region (D-loop). Samples from five localities in northern South Africa were obtained from archived collections. The two mitochondrial DNA gene regions were amplified and sequenced to provide population summary statistics, differentiation [proportion of the total genetic variation in a population relative to the total genetic variance of all the populations (FST), differentiation within populations among regions (ΦST)], genetic distance and structure. There was discernible genetic structure among the individuals, with two COI and six D-loop haplotypes belonging to two genetically different groups. There was population differentiation among regions (FST = 0.670; ΦST = 0.783; P < 0.01). However, there were low levels of differentiation among populations, as haplotypes were shared between distant populations. Adjacent populations were as divergent from each other as from distant populations. The results suggest that genetic introgression, most likely due to past migrations or recent unintentional translocations that include the animal trade, may have led to connectivity among populations.


Assuntos
DNA Mitocondrial , Galago/fisiologia , Animais , DNA Mitocondrial/genética , DNA Mitocondrial/isolamento & purificação , Ecossistema , Galago/classificação , Galago/genética , Fluxo Gênico , Genes Mitocondriais , Variação Genética , Genética Populacional , Haplótipos , Masculino , Família Multigênica , Filogenia , África do Sul
16.
Mol Biol Rep ; 48(1): 171-181, 2021 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-33275194

RESUMO

Cheetahs (Acinonyx jubatus) are listed as vulnerable on the International Union for Conservation of Nature Red List of Threatened Species. Threats include loss of habitat, human-wildlife conflict and illegal wildlife trade. In South Africa, the export of wild cheetah is a restricted activity under the Convention on International Trade in Endangered Species of Wild Fauna and Flora (CITES), however, limited legal trade is permitted of animals born to captive parents. To effectively monitor the legal and illegal trade in South Africa, it was thus essential to develop a validated molecular test. Here, we designed a single nucleotide polymorphism (SNP) array for cheetah from Double Digest Restriction Associated DNA sequencing data for individual identification and parentage testing. In order to validate the array, unrelated individuals and 16 family groups consisting of both parents and one to three offspring were genotyped using the Applied Biosystems™ QuantStudio™ 12K Flex Real-Time PCR System. In addition, parentage assignments were compared to microsatellite data. Cross-species amplification was tested in various felids and cheetah sub-species in order to determine the utility of the SNP array in other species. We obtained successful genotyping results for 218 SNPs in cheetah (A. j. jubatus) with an optimal DNA input concentration ranging from 10 to 30 ng/µl. The combination of SNPs had a higher resolving power for individual identification compared to microsatellites and provided high assignment accuracy in known pedigrees. Cross-species amplification in other felids was determined to be limited. However, the SNP array demonstrated a clear genetic discrimination of two cheetah subspecies tested here. We conclude that the described SNP array is suitable for accurate parentage assignment and provides an important traceability tool for forensic investigations of cheetah trade.


Assuntos
Acinonyx/genética , Conservação dos Recursos Naturais , Genoma/genética , Genômica , Animais , Animais Selvagens/genética , Comércio , Ecossistema , Espécies em Perigo de Extinção , Genótipo , Humanos , Polimorfismo de Nucleotídeo Único/genética , África do Sul
17.
J Genet ; 992020.
Artigo em Inglês | MEDLINE | ID: mdl-32366731

RESUMO

Temminck's ground pangolin (Smutsia temminckii) is one of four species of pangolin, endemic to Africa. Two of the African pangolin species are listed as vulnerable and two are listed as endangered on the International Union for Conservation of Nature Red List of Threatened Species due to their ongoing exploitation for traditional medicine and bushmeat. In this study, we developed 30 species-specific short-tandem repeats (STRs) in Temminck's ground pangolin using next-generation sequencing. The markers were also optimized for crossamplification in other African species. All the markers amplified successfully in Temminck's ground pangolin with allelic polymorphisms observed in 87% of the markers in giant pangolin (S. gigantea) whereas 60% of the markers were amplified polymorphic loci in both whitebellied pangolin (Phataginus tricuspis) and black-bellied pangolin (P. tetradactyla). Analysis of diversity estimates showed moderate levels of variability in Temminck's ground pangolin (Na = 5; Ho = 0.559), giant pangolin (Na = 4.909; Ho = 0.514) and white-bellied pangolin (Na= 2.686; Ho = 0.541) with lower values being observed in black-bellied pangolin (Na = 3; Ho = 0.242). This study provides data of the first available STR markers which was amplified in all four African pangolin species that can now be used in conservation genetic and evolutionary aspects of population histories.


Assuntos
Repetições de Microssatélites/genética , Pangolins/genética , África , Animais , Espécies em Perigo de Extinção , Evolução Molecular , Amplificação de Genes , Marcadores Genéticos , Genética Populacional , Sequenciamento de Nucleotídeos em Larga Escala , Mamíferos/genética , Polimorfismo Genético , Análise de Sequência de DNA
18.
Ticks Tick Borne Dis ; 11(2): 101358, 2020 03.
Artigo em Inglês | MEDLINE | ID: mdl-31870636

RESUMO

Recently reported substantial genetic diversity within Theileria equi 18S rRNA gene sequences has led to the identification of five genotypes A, B, C, D, and E, complicating molecular and serological diagnosis. In addition, T. haneyi has lately been reported as a species closely related to the T. equi 18S rRNA genotype C (Knowles et al., 2018). Theileria spp. of this group have a monophyletic origin and are therefore referred to as Equus group to distinguish them from the remaining Theileria lineages (Jalovecka et al., 2019). In this study, we report on the development of genotype-specific quantitative real-time PCR assays capable of detecting and distinguishing between each parasite genotype. Alignment of complete 18S rRNA sequences available on GenBank allowed for the design of a single primer pair and five TaqMan minor groove binder (MGB™) probes specific for each genotype (A-E). The assays, evaluated as qPCR simplex and two qPCR multiplex formats (Multiplex EP-ABC and Multiplex EP-DE), were shown to be both efficient and specific in the detection of T. equi genotypes. The developed qPCR assays were used to study (i) the intra-specific diversity of parasite genotypes within horse and zebra, (ii) the inter-specific differences in parasite genotype diversity in horses as compared to zebra, and (iii) the geographic distribution of T. equi 18S rRNA genotypes in South Africa. In addition, (iv) the presence of T. haneyi in South Africa was evaluated. An assessment of 342 equine field samples comprising 149 field horses, 55 racehorses, and 138 wild zebra confirmed the previously reported presence of T. equi 18S rRNA genotypes A, B, C, and D, and absence of genotype E in South African equids. Theileria equi genotypes A, B, C, and D, were detected in zebra, whereas only genotypes A, C and D, could be identified in field horses, and only genotypes A and C in racehorses. Genotypes B and D were the dominant genotypes identified in zebra in South Africa, while horses were predominantly infected with T. equi genotypes A and C. The greater diversity of T. equi genotypes in zebra suggests that it is an ancestral host for this piroplasmid lineage. Importantly, evidence is presented that each identified T. equi genotype segregates independently in each of the three studied equid populations reinforcing the notion that they represent individual separate entities corresponding to species. Preliminary investigations of the relationship between T. equi genotype C infections and Theileria haneyi, suggest that in addition to the five currently known T. equi genotypes, South African equids are also infected with T. haneyi.


Assuntos
Equidae , Doenças dos Cavalos/epidemiologia , Theileria/genética , Theileriose/epidemiologia , Animais , Sequência de Bases , Genótipo , Doenças dos Cavalos/parasitologia , Cavalos , RNA de Protozoário/análise , RNA Ribossômico 18S/análise , Alinhamento de Sequência/veterinária , África do Sul/epidemiologia , Theileriose/parasitologia
19.
Artigo em Inglês | MEDLINE | ID: mdl-31762360

RESUMO

Greater bushbabies, strepsirrhine primates, that are distributed across central, eastern and southern Africa, with northern and eastern South Africa representing the species' most southerly distribution. Greater bushbabies are habitat specialists whose naturally fragmented habitats are getting even more fragmented due to anthropogenic activities. Currently, there is no population genetic data or study published on the species. The aim of our study was to investigate the genetic variation in a thick-tailed bushbaby, Otolemur crassicaudatus, population in the Soutpansberg mountain range, Limpopo Province, South Africa. Four mitochondrial regions, ranging from highly conserved to highly variable, were sequenced from 47 individuals. The sequences were aligned and genetic diversity, structure, as well as demographic analyses were performed. Low genetic diversity (π = 0.0007-0.0038 in coding regions and π = 0.0127 in non-coding region; Hd = 0.166-0.569 in coding regions and Hd = 0.584 in non-coding region) and sub-structuring (H = 2-3 in coding regions and H = 4 in non-coding region) was observed with two divergent haplogroups (haplotype pairwise distance = 3-5 in coding region and 6-10 in non-coding region) being identified. This suggests the population may have experienced fixation of mitochondrial haplotypes due to limited female immigration, which is consistent with philopatric species, that alternative haplotypes are not native to this population, and that there may be male mobility from adjacent populations. This study provides the first detailed insights into the mitochondrial genetic diversity of a continental African strepsirrhine primate and demonstrates the utility of mitochondrial DNA in intraspecific genetic population analyses of these primates.


Assuntos
DNA Mitocondrial/genética , Galago/genética , Genética Populacional , Genoma Mitocondrial/genética , Animais , Feminino , Variação Genética/genética , Masculino , Filogenia , África do Sul
20.
Infect Genet Evol ; 78: 104118, 2020 03.
Artigo em Inglês | MEDLINE | ID: mdl-31734289

RESUMO

Toll-like receptors (TLR) are a family of proteins that signal activation of the innate immune response through the recognition of a variety of pathogen molecular compounds. Here, we characterized the complete TLR9 gene in Cape mountain zebra (Equus zebra zebra) from three populations in South Africa and compared sequences to a variety of horse and donkey breeds. Overall, we identified six single nucleotide polymorpHisms (SNPs). A single SNP (G586S) was non-synonymous, whereas the remaining SNPs were synonymous. The G586S alteration was detected in Cape mountain zebra populations with varying frequency. In addition, adaptive diversity was found to be discordant with variation based on neutral markers. The mutation is unique to the Cape mountain zebra when compared to other equid species. The structure of TLR9 is relatively conserved and the resulting amino acid substitution was found to have minimal interaction with active sites in the protein. Future studies can explore the effects of this potentially functional mutation which will contribute to our understanding of genetic diversity within adaptive sites of the Cape mountain zebra genome.


Assuntos
Equidae/genética , Receptor Toll-Like 9/genética , Substituição de Aminoácidos , Animais , Éxons , Cavalos/genética , Mutação , Polimorfismo de Nucleotídeo Único , África do Sul
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