Search Results (97)

This study evaluated the genetic variability and traceability potential of farmed European sea bass (Dicentrarchus labrax) and gilthead seabream (Sparus aurata) populations from a fish farm located in Petrosino (Marsala, Sicily) (FAO 37), using microsatellite markers. A total of 64 D. labrax and 63 S. aurata individuals were genotyped with species-specific multiplex panels (9 and 10 loci, respectively). High levels of polymorphism were observed in both species, with an average of 12 alleles per locus in D. labrax and 9.1 alleles per locus in S. aurata. Mean observed heterozygosity (Ho) was 0.530 in D. labrax and 0.459 in S. aurata, while expected heterozygosity (He) reached 0.762 and 0.702, respectively. The fixation index (F) indicated moderate heterozygote deficiency in both populations (0.320 in D. labrax and 0.352 in S. aurata). Significant deviations from Hardy–Weinberg equilibrium were detected at most loci in both species, suggesting non-random mating, genetic drift, or population substructure. The probability of identity (PI) values across loci confirmed the high discriminatory power of the microsatellite panels, supporting their suitability for individual identification and genetic traceability applications in aquaculture. Overall, the results highlight that, despite substantial genetic variability, the observed heterozygote deficiency and deviations from equilibrium may reflect suboptimal breeding management practices. These findings underline the importance of implementing regular genetic monitoring and integrating molecular tools into broodstock management to maintain genetic diversity, reduce inbreeding, and support sustainable aquaculture production. Full article

Assessing genetic structure is important for conserving endangered freshwater fishes inhabiting fragmented river systems. Pseudopungtungia nigra, a Korean endemic species, occurs in several isolated drainages, but its mitochondrial population structure has not been fully evaluated. In this study, we analyzed mitochondrial cytochrome b (cytb) sequences from 80 individuals across eight populations to examine genetic diversity, haplotype composition, and population differentiation. A total of 25 haplotypes were detected, indicating relatively high diversity at the species level. However, diversity was uneven among populations: the Mangyeonggang (MG) population contained only two haplotypes, both of which were not found in the other populations, and showed the lowest haplotype and nucleotide diversity among the sampled populations. Multiple analyses, including pairwise differentiation, haplotype network reconstruction, principal coordinates analysis, and AMOVA, consistently identified MG as the most divergent population. The mitochondrial pattern was also concordant with previously reported microsatellite-based structure, supporting a major division between MG and the remaining populations. These findings indicate that P. nigra preserves substantial diversity overall, whereas the MG population showed a restricted and population-specific cytb haplotype composition. This study provides a genetic basis for defining conservation units and for guiding restoration and management strategies in this endangered species. Full article

Karyotypic diversification in birds is often masked by overall chromosomal conservation, yet the mechanisms driving lineage-specific variation remain poorly understood. Here, we demonstrate that genome evolution in Rallidae is shaped by dynamic, independent trajectories of chromosomal reorganization, despite the retention of general avian architectural features. By integrating cytogenetic and molecular mapping data from two Neotropical species, Fulica rufifrons Philippi & Landbeck, 1861 (Red-fronted Coot) and Aramides ypecaha Vieillot, 1819 (Giant Wood Rail), we show that repetitive DNA expansion and heterochromatinization contribute to karyotype variability and sex chromosome differentiation. The contrasting structure and heterochromatic composition of the W chromosome between these species reveal that sex chromosomes evolve rapidly and independently, driven by lineage-specific accumulation of repetitive elements. Moreover, the variation in microsatellite distribution, especially the distinct localization of motifs on macro- and microchromosomes, underscores the independent and dynamic evolution of repetitive sequences. Our findings collectively indicate that chromosomal rearrangements, along with the amplification and redistribution of repetitive DNA, are contributing factors of genomic diversification in Rallidae, offering new insights into the mechanisms underlying karyotype evolution and sex chromosome differentiation in birds. Full article

A simple, fast, and cost-effective organic solvent-based protocol was developed for DNA extraction from deer antlers and prepared trophy skulls, eliminating the need for commercial kits or cryogenic grinding. The method combines bead-based mechanical homogenization with a 4 h enzymatic digestion in EDTA buffer containing N-lauryl sarcosine and Proteinase K, followed by phenol–chloroform–isoamyl alcohol purification and centrifugal filtration. DNA quality and quantity were evaluated using agarose gel electrophoresis, Qubit fluorometry, and Nanodrop spectrophotometry. The protocol was tested on 60 samples, comprising 30 antlers and 30 pedicle parts from prepared trophy skulls of roe deer (Capreolus capreolus), fallow deer (Dama dama), and red deer (Cervus elaphus). To assess suitability for downstream applications, species-specific microsatellite markers were amplified using multiplex PCR, successfully generating complete genotypes from all 60 samples. These results, along with a demonstrated case study, confirm that the developed protocol provides high-quality DNA suitable for molecular genetic investigations, enabling reliable genotyping from small amounts of both antler and processed trophy materials in forensic and conservation contexts. Full article

Background/Objectives: Habitat degradation and fragmentation reduce population size, genetic diversity, and connectivity, increasing extinction risk in small and isolated populations. Coastal wetlands of northwestern Peru have undergone extensive anthropogenic modification, yet the genetic and ecological status of resident carnivore populations remains poorly documented. This study aimed to assess genetic diversity, relatedness, demographic signals, and diet composition of a Pampas cat (Leopardus garleppi) population inhabiting the Mangroves San Pedro de Vice (MSPV), a Ramsar-listed coastal wetland. Methods: We combined noninvasive fecal genotyping using eight nuclear microsatellite loci with vertebrate DNA metabarcoding. Scat samples were collected across three field seasons (2019–2021). Individual identification, genetic diversity metrics, genetic mark–recapture estimation of census size (Nc), effective population size (Ne), bottleneck tests, and relatedness analyses were performed to evaluate population status and kin structure. Dietary composition was characterized using metabarcoding and assessed for sex-specific differences. Results: Sixty-eight scats yielded multilocus genotypes for nine individuals (six males, three females). Genetic analyses revealed moderate diversity (mean allelic richness = 3.47; observed heterozygosity = 0.69; expected heterozygosity = 0.58) and evidence consistent with a recent genetic bottleneck. Genetic mark–recapture analyses estimated a small census size (Nc = 9; 95% CI: 7.0–9.0), while the effective population size was markedly low (Ne = 2.4; 95% CI: 1.5–7.4), yielding an Ne/Nc ratio of ~0.27. Multiple first-order kin dyads were detected, indicating strong local kin structure and limited external recruitment. Metabarcoding identified eight vertebrate prey species, with diet dominated by the native rodent Aegialomys xanthaeolus. No significant sex-specific differences in diet composition were detected. Conclusions: The MSPV Pampas cat population represents a small, kin-structured range-edge population showing signatures consistent with recent genetic erosion and restricted connectivity. These patterns align with isolation in a degraded coastal wetland landscape, highlighting the importance of habitat protection, prey resource conservation, and restoration of functional connectivity to support long-term population persistence. Full article

How many founders are required for insects and other organisms to establish new populations is a fundamental question in invasion biology. We investigated the population establishment process of a parasitoid wasp, Monodontomerus sp., which was first recorded in Japan in 2000. Field surveys conducted in this study showed that the parasitism rate has been increasing in recent years. Morphological and molecular analyses suggested that the parasitoid species is M. obscurus, or a closely related lineage derived from it, which newly invaded Japan. To examine genetic variation during the early stage of invasion, we developed microsatellite DNA markers and conducted population genetic analyses. The results revealed extremely low genetic diversity: most loci were monomorphic, polymorphism was restricted to loci with long repeat motifs, and the allele frequencies of these loci were dominated by single alleles. A minimum spanning network based on microsatellite genotypes exhibited a star-like pattern. These results based on genome-wide microsatellite data indicate that the present population was founded by very few individuals, most likely a single female or an effectively single genetic lineage, and novel genotypes arose through post-invasion mutations. Our study provides rare empirical evidence for single-female founding under natural conditions, and highlights how species-specific life-history and genetic systems can enable successful invasion despite extreme bottlenecks. Full article

When analyzing the long-term viability of small, declining populations, it is essential to recognize that inbreeding and the erosion of genetic diversity are primarily driven by the effective population size, which is often a fraction of the total census count. The globally endangered Lear’s macaw (Anodorhynchus leari) is a restricted-range species endemic to the Caatinga ecoregion in NE Brazil. This species was only known in captivity due to wildlife illegal trade, until 1978, when a small population close to extinction was discovered in the wild, estimated at ca. 60 individuals in 1983. Conservation efforts have allowed for population recovery in recent decades, reaching a population of ca. 2273 individuals in 2022. Given these drastic population changes, a genetic assessment is important to empower conservation strategies with knowledge about the level of genetic variability, population genetic structure, inbreeding levels, and demographic history. We used a set of eight species-specific microsatellites to provide the first genetic assessment of the wild population of this species by genotyping non-invasive samples (molted feathers) collected in the known breeding and roosting sites of the species. Our results revealed a low effective population size (N_e = 49–80), which represents the main conservation concern. We also observed evidence of past bottlenecks. However, moderate levels of genetic diversity, no evidence of inbreeding, and a wide connectivity across the study area confirm a single population and set the ground for the potential natural recovery of this species and the recolonization of breeding sites across its former range. Full article

(1) Background: Rubus geoides Sm., a native species of southern Patagonia, faces increasing threats due to climate change and anthropogenic land-use changes. Historically widespread, its distribution has become restricted by overgrazing, urban expansion, extractive industries, and direct harvesting from natural populations driven by interest in its nutraceutical potential since the first European settlements. (2) Methods: To assess its resilience and conservation prospects, we analyzed the morphological variability, genetic diversity, and population structure, complemented by species distribution modeling under past and future climate scenarios. (3) Results: Our findings reveal moderate genetic differentiation and private alleles in specific populations, alongside significant variation in flowering phenology. Paternity analysis indicates a tendency toward self-pollination, although this conclusion is constrained by the limited number of microsatellite markers employed. These results suggest post-glacial dispersal patterns and highlight the species’ potential for expansion under certain climate scenarios. (4) Conclusions: This study provides critical insights for biodiversity conservation and sustainable land management, directly aligned with the UN Sustainable Development Goals SDG 15 (Life on Land). Indirectly, this study contributes to SDG 2 (Zero Hunger) by highlighting the importance of threatened species that hold value for human consumption and food security. Land-use changes, particularly mining and green hydrogen industry settlements, may represent stronger limitations to species expansion than climate change itself. Full article

Rumex crispus L. is a globally distributed invasive species that has naturalized in South Korea, where its use as a medicinal, edible, and ecological restoration resource continues to expand. However, its genetic background remains insufficiently understood, underscoring the need for species-specific molecular markers to enable accurate assessments of intraspecific genetic diversity and population structure. Using 19 newly developed microsatellite markers, we analyzed 120 plants from 6 populations in the riparian zone. A total of 166 alleles were detected, with a mean polymorphism information content of 0.637. Across the six populations, genetic diversity analysis showed mean observed (Ho = 0.304) and expected (He = 0.588) heterozygosity values indicative of heterozygote deficiency (inbreeding coefficient F_IS = 0.456–0.559). Genetic differentiation was low in AMOVA (10%) and F_ST (0.048–0.120) but higher in Jost’s D (0.096–0.342). STRUCTURE analysis identified two major genetic clusters (ΔK = 2), and spatial Bayesian clustering revealed six distinct genetic units (K = 6), suggesting that partial barriers to gene flow may have influenced population structure. These findings provide essential genetic insights that can support the effective control of R. crispus spread and its potential use as a valuable plant resource. Full article

The complex life cycle, high reproductive potential and ability to quickly develop resistance to insecticides are key factors contributing to the destructiveness of the peach–potato aphid (Myzus persicae Sulzer) among pest species. Monitoring its population dynamics at a large scale allows us to better understand M. persicae biology and take relevant measures for pest management. For this purpose, reliable molecular tools are needed. Based on the analysis of 128,362 microsatellite loci, we developed four multiplex assays including 49 comprehensively characterised SSR markers. Internal validation confirmed the species specificity and low genotyping error (e_a = 0.8%, e_l = 0.99%, e_obs = 22.7%) of the assays. A total of 194 alleles were identified (mean = 4 alleles per locus, range = 2–8 alleles per locus) within a group of 365 aphid accessions collected in the Vysočina region (Czechia). The studied aphid population showed the typical characteristics expected of the species with clonal or partially clonal reproduction (heterozygote excess, negative F_IS, moderate-to-high linkage disequilibrium (LD), and distortion of the H-W equilibrium for most of the loci), and did not exhibit any stratification on a spatiotemporal level. Owing to the high discriminatory power of the markers, we discovered that the population sample was founded upon a small number of fundatrices, as only five dominating lineages comprising over 70% of all accessions were identified. In conclusion, this study identified a significant number of new high-quality markers with the high discriminatory power necessary for revealing the population structure and dynamics of M. persicae, which holds considerable potential in both general biological and agricultural research. Full article

Genetic variability in terrestrial mammals is essential for understanding population and evolutionary dynamics, as well as for establishing effective strategies in conservation biology. This comprehensive review aimed to critically analyze invasive and non-invasive techniques used to assess genetic variability in wild terrestrial mammals. Using the PICO (Population, Intervention, Comparison, Outcome) format and following PRISMA guidelines, a comprehensive literature search was conducted in Web of Science, Scopus and Science Direct databases, including articles published in English from January 2015 to April 2025. Thirty-one experimental studies were selected that met specific criteria related to genetic evaluation using invasive (direct blood or tissue collection) and non-invasive (stool, hair and saliva collection) techniques. The results indicate that invasive techniques provide samples of high genetic quality, albeit with important ethical and animal welfare considerations. In contrast, non-invasive techniques offer less disruptive methods, although they present significant challenges in terms of quantity and purity of DNA obtained, potentially affecting the accuracy and confidence of genetic analysis. Detailed analysis of selected studies showed diverse patterns of heterozygosity and inbreeding coefficients between different taxonomic orders (Carnivora, Artiodactyla, Proboscidea, Primates and Rodentia). In addition, the main anthropogenic threats and current conservation strategies implemented in different species were identified. An overall genetic variability ranging from high to moderate was observed, with large species being more vulnerable to genetic reduction due to changes in habitat and human activities. Rather than a static comparison, our synthesis traces a clear methodological arc from small short tandem repeats (STR, or microsatellites) panels towards SNP-based approaches enabled by next-generation sequencing, including reduced representation (ddRAD), amplicon panels (GT-seq), and hybridisation capture tailored to degraded DNA from hair, faeces, and environmental substrates. Over 2015–2025, study designs shifted from presence/absence and coarse diversity estimates to robust inference of relatedness, assignment, effective population size, and gene flow using hundreds–thousands of SNPs and genotype-likelihood frameworks tolerant of allelic dropout and low coverage. Laboratory practice converged on multi-tube replication, synthetic blocking oligos, and capture-based enrichment; bioinformatics adopted probabilistic genotype calling, error-aware filtering, and replication-based consensus. This review provides a solid basis for optimizing genetic sampling methods, allowing for more ethical and efficient studies. Furthermore, it contributes to strengthening conservation strategies by underlining the importance of adapting the sampling method to the biological and ecological particularities of each species studied. Ultimately, these findings can significantly improve genetic conservation decision-making, benefiting the sustainability and resilience of wild land mammal populations. Full article

Background/Objectives: The mutational dynamics of microsatellites over deep evolutionary timescales are poorly understood. This study aims to elucidate the life history of trinucleotide microsatellites by tracing orthologous loci across divergent vertebrate lineages and characterizing their mutational pathways. Methods: We developed a bioinformatic framework for identifying orthologous microsatellite loci using conserved flanking sequences. This approach was applied to three trinucleotide microsatellites located in exonic, intronic, and intergenic regions, respectively. These loci were amplified and sequenced across 126 individuals representing 64 vertebrate species, whose divergence times range from 6 to 150 million years ago (MYA). Results: Flanking sequences proved essential for reliable orthology assignment, while repeat motifs revealed distinct mutational pathways. Microsatellite decay occurs through two primary mechanisms: the complete loss of dominant repeats or their progressive reduction to solitary units (≤1 repeat). This degeneration process is facilitated by cryptic simple sequences (CSS), which act as genomic catalysts promoting birth–death transitions. Large intra-motif deletions were identified as the key mutational event driving contractions and eventual locus degeneration. Furthermore, mutational patterns were highly locus-specific, influenced by genomic context. Conclusions: Although the study focused on only three loci, limiting broader generalizations, our findings provide mechanistic insights into microsatellite evolution. These results establish a foundation for modeling complex microsatellite life histories and highlight the role of CSS in facilitating evolutionary turnover. Full article

The population size of black poplar (Populus nigra L.), once an important part of floodplain forests in the Czech Republic, has greatly declined due to human activity. In this study, we applied microsatellite (SSR) markers to identify species and assess genetic diversity, with the aim of supporting conservation of this endangered species. A total of 378 poplar trees were analyzed following field surveys. Five diagnostic SSR markers with species-specific alleles for P. deltoides Bartr. ex Marsh. enabled the identification of 39 interspecific hybrids, which were distinguished from native P. nigra. Thirteen SSR loci were used to evaluate genetic diversity among confirmed P. nigra individuals. The results revealed high genetic variation, with 66% of pairwise genotype comparisons differing at all loci. After excluding 45 genetically similar individuals, 292 genetically verified and polymorphic P. nigra trees were selected as potential sources of reproductive material. Genetic differentiation (Fst) was highest between P. nigra and P. deltoides (0.27), and lowest between reference Populus ×euroamericana clones and detected hybrid poplars (0.05) from natural localities. Distinct genetic structures were identified among P. nigra, P. deltoides, and hybrid individuals. These findings provide essential data for the protection, reproduction, and planting of black poplar. Full article

Bats are great models for studying repetitive DNAs due to their compact genomes and extensive chromosomal rearrangements. Here, we investigated the repetitive DNA content of two phyllostomid bat species, Artibeus lituratus (2nn = 30♀/31♂) and Carollia perspicillata (2n = 20♀/21♂), both harboring a multiple XY₁Y₂ sex chromosome system. Satellite DNA (satDNA) libraries were isolated and characterized, revealing four and ten satDNA families in A. lituratus and C. perspicillata, respectively. These sequences, along with selected microsatellites, were in situ mapped onto chromosomes in both species and phylogenetically related taxa. SatDNAs showed strong accumulation in centromeric and subtelomeric regions, especially pericentromeric areas. Cross-species mapping with C. perspicillata-derived probes indicated terminal localization patterns in other bat species, suggesting conserved distribution. Microsatellites co-localized with 45S rDNA clusters on the neo-sex chromosomes. Additionally, genomic hybridization revealed a male-specific signal on the Y₁ chromosome, pointing to potential sex-linked repetitive regions. These findings confirm that bat genomes display relatively low amounts of repetitive DNA compared to other mammals and underscore the role of these elements in genome organization and sex chromosome evolution in phyllostomid bats. Full article

This study investigates the genetic diversity and population structure of Castanopsis tribuloides, a vital tree species in Asian forest ecosystems. Understanding the genetic patterns of keystone forest species provides critical insights into forest resilience and ecosystem function and informs conservation strategies. We analyzed population samples collected from three distinct locations within Doi Suthep Mountain in northern Thailand using Short Tandem Repeat (STR) markers to assess both intra- and inter-population genetic relationships. DNA was extracted from leaf samples and analyzed using a panel of polymorphic microsatellite loci specifically optimized for Castanopsis species. Statistical analyses included the assessment of forensic parameters (number of alleles, observed and expected heterozygosity, gene diversity, polymorphic information content), population differentiation metrics (G_ST), inbreeding coefficients (F_IS), and gene flow estimates (N_m). We further examined population history through bottleneck analysis using three models (IAM, SMM, and TPM) and visualized genetic relationships through principal coordinate analysis and cluster analysis. Our results revealed significant patterns of genetic structuring across the sampled populations, with genetic distance metrics showing statistically significant differentiation between certain population pairs. The PCA and cluster analyses confirmed distinct population groupings that correspond to geographic distribution patterns. These findings provide the first comprehensive assessment of C. tribuloides population genetics in this region, establishing baseline data for monitoring genetic diversity and informing conservation strategies. This research contributes to our understanding of how landscape features and ecological factors shape genetic diversity patterns in essential forest tree species, with implications for managing forest genetic resources in the face of environmental change. Full article