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Comparative genomic analysis of Acer tsinglingense and A. davidii provides insights into nervonic acid biosynthesis, population evolution and genome vulnerability of endangered A. tsinglingense.

Global biodiversity is facing threats from climate change, habitat fragmentation, and anthropogenic activities-pressures that particularly endanger endemic and narrowly distributed species. In this study, the high-quality chromosome-level genomes of two ecologically divergent maples were assembled: the endangered and range-restricted Acer tsinglingense (791.40 Mb) and its widespread congener Acer davidii (1291.99 Mb). Phylogenomic analysis indicates that the two species diverged ~16.3 million years ago, with A. tsinglingense showing notable gene family expansions in secondary metabolite pathways. Notably, the 3-ketoacyl-CoA synthase gene family, which is involved in nervonic acid biosynthesis, underwent significant expansion and tandem duplication in A. tsinglingense, exhibiting high expression in buds. Population genomic analysis revealed that, compared with the widely distributed A. davidii, A. tsinglingense possesses lower genetic diversity, higher harmful mutation load, and signatures of a severe population bottleneck during the Late Pleistocene. Genome-environment association analysis further identified climate-adaptive genomic variations linked to five key environmental factors and projected potential genomic offsets under future climate scenarios. The southern lineage of A. tsinglingense exhibited greater climate sensitivity and genomic vulnerability under strong selective pressures, underscoring its importance as a conservation priority. Our research reveals that metabolic specializations in A. tsinglingense (such as the synthesis of nervonic acid) may confer competitive advantages in specific habitats. However, factors including its restricted distribution, historical population bottlenecks, and accumulated genetic load severely constrain its evolutionary potential to cope with rapid climate change. These findings emphasize the importance of elucidating the genomic basis and mechanisms of endangerment in metabolically specialized and threatened plant species to inform effective conservation strategies.

Genome, Plant

Genome-wide SNP data reveal geographic structure and landscape-associated genomic differentiation in a widespread lizard in arid Eastern Central Asia.

Arid landscapes provide important systems for examining how geographic structure and environmental heterogeneity shape genomic differentiation. In topographically complex desert regions, however, it remains challenging to determine whether population structure primarily reflects landscape resistance, geographic distance, or contemporary environmental variation. Here, we use genome-wide SNP data to investigate population structure, phylogenetic relationships, historical gene flow, demographic history, and landscape correlates of genomic differentiation in the variegated racerunner (Eremias vermiculata), a widespread lacertid lizard across arid Eastern Central Asia. Analyses of 164 individuals recovered six geographically structured nuclear clusters associated with major desert basins and mountain-bounded regions. Nuclear phylogenies resolved two broad regional clades corresponding to northeastern and southwestern parts of the species' range, while PCA and ADMIXTURE analyses recovered six finer-scale genetic clusters. Mitochondrial phylogenies, based on combined NCBI-derived Cyt b and COI sequences from the same individuals, recovered four deeper maternal lineages. These patterns indicate overall phylogeographic agreement between nuclear and mitochondrial datasets, with genome-wide SNPs providing finer-scale resolution of population structure. Demographic reconstructions further uncovered regionally heterogeneous Late Pleistocene histories among clusters, including signals of expansion, stability, and decline. Landscape genomic analyses revealed that genomic differentiation is primarily associated with landscape resistance, particularly elevation and land cover, as well as geographic distance, whereas contemporary environmental variables explained comparatively little variation after controlling for spatial structure. Together, our results suggest that genomic differentiation in E. vermiculata reflects the interplay of persistent landscape configuration, historical connectivity, and region-specific demographic histories across arid Eastern Central Asia. More broadly, this study highlights the value of integrating phylogeographic and landscape genomic approaches for understanding population differentiation and evolutionary history in topographically heterogeneous desert ecosystems.

Arid Eastern Central Asia

Population history rather than tree age contributes to the evolutionary importance of ancient trees in an endangered conifer.

Ancient trees are in global decline and face increasing conservation challenges. Their exceptional longevity has fostered the view that they are genetic reservoirs, yet whether old age is synonymous with unique genetic variation remains unclear. Here we assembled a ~8-Gb chromosome-level reference genome for the critically endangered conifer Glyptostrobus pensilis, now largely restricted to southern China with scattered populations in Vietnam and Laos, and resequenced 147 individuals, including 64 ancient (>100 years old and persisting in human-dominated landscapes), 33 wild and 50 recently cultivated individuals. Ancient individuals comprised both likely natural relics and historically introduced individuals and formed two deeply divergent lineages and one ancestral-admixed group, each with distinct demographic histories of prolonged contraction and genomic erosion. Lineage identity explained more variation in genome-wide diversity, inbreeding and genetic load than the three conservation types, despite broad differences in age structure. Rare-allele analyses revealed pronounced heterogeneity among ancient trees: only relic and ancestral-origin individuals from high-diversity lineages contributed substantial unique variation, much of which is poorly represented in wild and cultivated populations. Together, our findings suggest that ancient trees are not uniformly genetically irreplaceable and that, at least in this conifer, evolutionary importance is shaped more strongly by population history than by age alone.

Endangered Species

Conservation genomics of a threatened subtropical Rhododendron species highlights the distinct conservation actions required in marginal and admixed populations.

With the impact of climate change and anthropogenic activities, the underlying threats facing populations with different evolutionary histories and distributions, and the associated conservation strategies necessary to ensure their survival, may vary within a species. This is particularly true for marginal populations and/or those showing admixture. Here, we re-sequence genomes of 102 individuals from 21 locations for Rhododendron vialii, a threatened species distributed in the subtropical forests of southwestern China that has suffered from habitat fragmentation due to deforestation. Population structure results revealed that R. vialii can be divided into five genetic lineages using neutral single-nucleotide polymorphisms (SNPs), whereas selected SNPs divide the species into six lineages. This is due to the Guigu (GG) population, which is identified as admixed using neutral SNPs, but is assigned to a distinct genetic cluster using non-neutral loci. R. vialii has experienced multiple genetic bottlenecks, and different demographic histories have been suggested among populations. Ecological niche modeling combined with genomic offset analysis suggests that the marginal population (Northeast, NE) harboring the highest genetic diversity is likely to have the highest risk of maladaptation in the future. The marginal population therefore needs urgent ex situ conservation in areas where the influence of future climate change is predicted to be well buffered. Alternatively, the GG population may have the potential for local adaptation, and will need in situ conservation. The Puer population, which carries the heaviest genetic load, needs genetic rescue. Our findings highlight how population genomics, genomic offset analysis, and ecological niche modeling can be integrated to inform targeted conservation.

Rhododendron

Global diversity and evolution of Salmonella enterica serovar Panama: a genomic epidemiology study.

BACKGROUND: Non-typhoidal Salmonella is a globally important bacterial pathogen, typically associated with foodborne gastrointestinal infection. Some non-typhoidal Salmonella serovars can also colonise typically sterile sites in people to cause invasive non-typhoidal Salmonella disease. Salmonella enterica serovar Panama is responsible for a substantial number of cases of human bloodstream infection, but despite its global dissemination, numerous outbreaks, and a reported association with invasive non-typhoidal Salmonella disease, S enterica serovar Panama (S Panama) is understudied. We aimed to describe the genomic epidemiology and evolutionary history of S Panama to provide a vital baseline of understanding for this globally important serovar. METHODS: In this genomic epidemiology study, we analysed S Panama genomes derived from historical collections, national surveillance datasets, and publicly available epidemiological and whole-genome sequencing data which span the years 1931-2019. Maximum likelihood and Bayesian phylodynamic approaches were used to investigate population structure and evolutionary history and to infer geotemporal dissemination. A combination of different bioinformatic approaches with short-read and long-read data were used to characterise geographical and clade-specific trends in antimicrobial resistance (AMR) and genetic markers for invasiveness. FINDINGS: We analysed 836 S Panama genomes, of which 559 (67%) were sequenced as part of this study. The collection represents all inhabited continents and includes isolates collected between 1931 and 2019. We identified the presence of four geographically linked S Panama clades (C1 [ie, the Latin America and the Caribbean clade; n=338], C2 [ie, the European clade; n=124], C3 [ie, the Martinique clade; n=131], and C4 [ie, the Asia and Oceania clade; n=104]) and regional trends in AMR profiles. Most isolates (715 [86%] of 836) were pan-susceptible to antibiotics and belonged to clades circulating in Latin America and the Caribbean (64%, n=458). Most antibiotic-resistant isolates in our collection (113 [93%] of 121) fell within clades C4 (ie, the Asia and Oceania clade) and C2 (ie, the European clade), the latter of which had the highest invasiveness index values based on the conservation of 196 extraintestinal predictor genes. INTERPRETATION: This first large-scale phylogenetic analysis of S Panama has revealed important information about the population structure, AMR, global ecology, and genetic markers of invasiveness of the identified genomic subtypes. Our findings provide an important baseline for understanding S Panama infection. The presence of multidrug-resistant clades with elevated invasiveness index values should be monitored through ongoing surveillance, as such clades could pose an increased public health risk. FUNDING: UK Research and Innovation Global Challenges Research Fund and Biotechnology and Biological Sciences Research Council, UK Medical Research Council, Wellcome Trust, John Lennon Memorial Scholarship, Institut Pasteur, Santé publique France, Fondation Le Roch-Les Mousquetaires, Investissement d'Avenir Programme, and Australian National Health and Medical Research Council.

Humans

RePo index: a multidimensional framework to quantify genetic resilience in data-limited amphibian faunas.

This study explores the resilience of Chilean amphibians to environmental disturbances through an integrative approach that combines ecological, demographic, bibliometric, and molecular information. A total of 58 species distributed across 14 genera and 9 families were evaluated via the resilience potential (RePo) index, which incorporates eleven criteria grouped into five dimensions: distribution, population trends, emerging diseases, evolutionary history, and genetic records. The results revealed high ecological vulnerability: 83% of the species were classified as non resilient (45% with no resilience and 38% with low resilience), and none reached the high-resilience category. At the family level, Telmatobiidae presented the lowest resilience values, whereas Leptodactylidae presented the highest. At the genus level, Insuetophrynus was identified as the most vulnerable taxon, with no molecular records and an extremely restricted distribution. In contrast, species such as Rhinella spinulosa and Pleurodema thaul presented moderate resilience, suggesting greater adaptive potential and relevance for functional studies. From a bibliometric perspective, a bias toward classical research topics (distribution, physiology, and taxonomy) was detected, with limited representation of integrative approaches such as genetic conservation or climate change. The conceptual modularity in the literature was low (Q = 0.1328), indicating weak thematic differentiation and little integration of omics tools. Most species lack transcriptomic and genomic data, severely limiting the assessment of their adaptive mechanisms. In this context, the RePo index has emerged as an integrative tool useful for operationalizing concepts such as evolutionarily significant units (ESUs) and management units (MUs), which are essential for evidence-based conservation. Finally, this study highlights the need to incorporate high-throughput sequencing (HTS) technologies and to participate in international initiatives, such as the Amphibian Genomics Consortium, as a strategic path forward for advancing adaptive conservation of Chilean amphibians.

Animals

The Baltic Sea: A Unique and Sensitive Ecosystem.

The Baltic Sea is a young, semi-enclosed brackish ecosystem shaped by postglacial history; restricted exchange with the North Sea; and strong gradients in salinity, temperature, and oxygen. These conditions have produced a species-poor but highly productive and ecologically important system. This review synthesizes evidence that Baltic populations persist not only through phenotypic plasticity but also through rapid evolutionary change, local adaptation, hybridization, and demographic history. Population genomic studies reveal sharp genetic differentiation between Baltic and Atlantic populations in many taxa, often across the Danish Straits, and fine-scale structuring within the Baltic itself. Case studies of eelgrass, bladderwrack, blue mussels, Baltic clam, cod, flounder, and herring illustrate how clonality, hybrid swarm formation, reproductive isolation, and habitat-specific selection shape resilience and vulnerability. Rapid warming, hypoxia, eutrophication, overfishing, and low functional redundancy increase ecosystem sensitivity. Long-term resilience will depend on protecting locally adapted populations and integrating genomic knowledge into ecosystem-based management and conservation.

Journal Article

Genome sequencing and population genomics provide insights into the demographic history, genetic load, and local adaptation of an endangered Tertiary relict.

Endangered Tertiary relict trees represent an exceptional evolutionary heritage with small and isolated populations, yet little is known about how demographic history, local adaptation, and genetic load have affected their long-term survival and extinction risk. We performed whole-genome sequencing and population genomic analyses on Ulmus elongata L. K. Fu & C. S. Ding, an endangered Tertiary relict tree endemic to East Asia. By integrating genomes from U. elongata and seven other endangered trees from public databases, we identified rate-decelerated genes across endangered trees and genes under positive selection of U. elongata associated with tissue development, detoxification, and immune response, and signal transduction and regulation mechanisms potentially leading to endangered status. Demographic analyses revealed continuous population decline from the late Miocene to present, especially during the last glacial maximum (LGM) and last 10&#x2009;000&#x2009;years. Spearman correlation indicated a strong negative relationship between effective population size and human population density (rpopulation density&#x2009;=&#x2009;-0.90, P&#x2009;<&#x2009;0.001) as well as cropland use (rcropland use&#x2009;=&#x2009;-0.89, P&#x2009;<&#x2009;0.001). Genotype-environment association (GEA) analyses identified a set of candidate genes associated with temperature and precipitation, supporting a polygenic adaptation model in U. elongata. Overall, our findings underscore the severe population bottlenecks that have led to the fixation of strongly deleterious mutations and inbreeding, further compromising the adaptive potential and long-term viability of U. elongata. Furthermore, assessments of genomic vulnerability under future climate scenarios revealed higher genetic offsets in northern region of Fujian and Jiangxi populations, suggesting these regions require prioritized conservation efforts due to reduced adaptive capacity.

Endangered Species

National genomic projects in Asia and Africa: a review.

National genome projects (NGPs) are increasingly shaping precision medicine by improving representation of population-specific genetic diversity. This review compiles findings from NGPs across Asia and Africa, regions that remain underrepresented in global genomic databases despite their extensive demographic and genetic diversity. A total of 53 studies from 24 countries were identified to understand (1) the genomic approach utilized, (2) novel findings that have emerged, and (3) strategies for improving research in these regions. The NGPs implement population-based variome databases (20 NGPs), linear reference genome assemblies (8 NGPs), and graph-based pangenome assemblies (1 NGP). Novel variants ranged between 0.28% (China) and 19.6% (Iran), whereas rare variants accounted for up to 88.9% of the detected variants in the Chinese population. Each NGP documents its country's evolutionary and migration history, which impacts disease frequency and pharmacogenomic variants. Clinically, NGPs revealed strong population stratification in disease-associated and pharmacogenomic variants. For example, the&#xa0;GJB2&#xa0;rs72474224 hearing-loss variant ranged from 13% in Vietnam and 12% in Hong Kong to 0.0894% in Turkey, while the&#xa0;VKORC1&#xa0;rs9923231 pharmacogenomic variant reached 89.2% in Taiwan but was 20%-25% in European-related Russian subpopulations. These findings demonstrate that clinically relevant allele frequencies, pathogenicity assessments, and drug-response markers differ substantially across ancestries. This review highlights ongoing efforts and strategies to enhance the representativeness of genomic data through NGPs in Asia and Africa. We also suggest future directions for national projects, including integrating family-based studies, multi-omic data, and standardized pipelines to accelerate discovery and support the equitable implementation of precision medicine.

Humans

Genomic exploration of the journey of Plasmodium vivax in Latin America.

Plasmodium vivax is the predominant malaria parasite in Latin America. Its colonization history in the region is rich and complex, and is still highly debated, especially about its origin(s). Our study employed cutting-edge population genomic techniques to analyze whole genome variation from 620 P. vivax isolates, including 107 newly sequenced samples from West Africa, Middle East, and Latin America. This sampling represents nearly all potential source populations worldwide currently available. Analyses of the genetic structure, diversity, ancestry, coalescent-based inferences, including demographic scenario testing using Approximate Bayesian Computation, have revealed a more complex evolutionary history than previously envisioned. Indeed, our analyses suggest that the current American P. vivax populations predominantly stemmed from a now-extinct European lineage, with the potential contribution also from unsampled populations, most likely of West African origin. We also found evidence that P. vivax arrived in Latin America in multiple waves, initially during early European contact and later through post-colonial human migration waves in the late 19th-century. This study provides a fresh perspective on P. vivax's intricate evolutionary journey and brings insights into the possible contribution of West African P. vivax populations to the colonization history of Latin America.

Plasmodium vivax

Macrolide-resistant Mycoplasma pneumoniae resurgence in Chinese children in 2023: a longitudinal, cross-sectional, genomic epidemiology study.

BACKGROUND: After a prolonged period of low detection rates, Mycoplasma pneumoniae resurged in China, during September to November, 2023, raising global concern. This study aims to gain a better understanding of the genetic mechanisms underlying the 2023 increase in cases and the evolutionary dynamics of the epidemic populations, which has been previously hampered due to limited genomic data of this pathogen. METHODS: We sequenced 685 M pneumoniae isolates, including 248 isolates from 11 Chinese provinces and municipalities in 2023 and 437 isolates from Beijing (2013-22). By analysing these isolates and 436 publicly global sequences, we reconstructed the pathogen's evolutionary history using time-calibrated phylogenies and effective population size inference. We investigated potential genomic variations contributing to the 2023 resurgence through genome-wide association study and conducted phylogeographic analysis of the 2023 isolates across China. FINDINGS: Two macrolide-resistant epidemic clusters (T1-2-EC1 and T2-2-EC2) were responsible for the 2023 resurgence in China. Both clusters, having acquired the 23S ribosomal RNA A2063G mutation conferring macrolide resistance, emerged in approximately 1997 and 2014, respectively, and subsequently outcompeted their predecessor populations. This coincided with China's large-scale adoption of azithromycin for paediatric community-acquired pneumonia around the early 2000s. Aside from macrolide resistance, T1-2-EC1 independently acquired 17 clade-specific mutations and T2-2-EC2 four clade-specific mutations, which could further explain their increased competitiveness. Whole-genome analysis revealed no resurgence-specific mutations in the 2023 isolates. Phylogeographic analysis showed rapid mixing of T1-2-EC1 isolates between different sampled regions within China. INTERPRETATION: Our study provides evidence that the 2023 resurgence in China is a continuation of the pre-COVID epidemic, rather than emergence of novel variants. The high prevalence of macrolide resistance and rapid intranational spread emphasise the urgent need for enhanced global surveillance of this pathogen. FUNDING: National Key Research and Development Program of China, National Natural Science Foundation of China for Key Programs of China Grants, and Beijing High-Level Public Health Technical Talent Project.

Humans

Tracing the evolution and diversity of human parvovirus B19 across human history.

Human parvovirus B19 (B19V) is an ubiquitously spread, exclusively human pathogen, mainly posing risks to children, as well as pregnant and immunocompromised individuals. Despite evidence of B19V infection of human populations as far back as 7,000 years, the evolutionary history of B19V remains poorly understood. In this study, we present B19V genomic data from the remains of 53 globally distributed individuals spanning more than 8,000 years, including 7 children. Our findings suggest that the most recent common ancestor of all present B19V lineages existed around 12,000 years ago, at the end of the last Ice Age. Additionally, we identified an extinct Eurasian clade that participated in the recombination event that led to the emergence of B19V genotype 2 (GT-2). We date this event to &#x223c;3,200-1,800 BP, potentially in the greater Mediterranean area. Our study shows aspects of how ancient parvovirus variants arose, disseminated, and impacted human health through time.

ancient DNA

Mitogenomic Insights Into the Population Structure and Demographic History of Tree Shrews (Tupaia belangeri) in China.

The northern tree shrew (Tupaia belangeri) exhibits significant morphological and geographical variations, but its evolutionary history and subspecies boundaries remain controversial. Here, we analyzed the complete mitochondrial genomes of 63 individuals, representing 12 populations in China to study phylogenetic relationships, genetic diversity, and population history. Phylogenetic analysis consistently restored four mitochondrial branches with strong geographic structures and significant differences. The three lineages correspond to geographically restricted subspecies (T. b. tonquinia, T. b. modesta, and T. b. gaoligongensis), while individuals assigned to several traditional subspecies cluster in a broad mainland lineage (T. b. chinensis, T. b. yunalis, and T. b. yaoshanensis). The divergence time estimate places the origin of the main lineage in the Miocene, consistent with major tectonic and geomorphological events. Demographic analysis revealed different population histories, including varying degrees of expansion in recent continental and island lineages, as well as the long-term stability of T. b. gaoligongensis. Genetic diversity varied markedly among lineages, with the highest diversity observed in the T. b. gaoligongensis and the lowest diversity observed in the T. b. modesta. These findings demonstrate that landscape complexity and demographic history are key drivers of evolutionary diversification in T. belangeri, challenging classical morphology-based subspecies classifications and underscoring the need for comprehensive sampling across both domestic and international ranges.

Tupaia belangeri

First insights into the role of evolutionary history in shaping venom composition of Vipera ammodytes.

Understanding intraspecific venom variation requires distinguishing the contributions of neutral population history from natural selection. This study aims to determine whether venom variation in Vipera ammodytes species complex is structured across eight phylogenetic groups. Despite a complex evolutionary history, venom composition did not differ among phylogenetic groups within the analytical framework used, suggesting that shared ancestry alone does not explain venom variation. Whether local adaptation to environmental conditions explains the observed variation remains an open question for future studies.

Animals

Genomic analysis of xerophyte Salweenia species provides insights into the alpine dry-warm valleys divergence and survival history.

Salweenia species are evergreen shrubs capable of preventing desertification and maintaining the health of alpine dry-warm ecosystems in the Hengduan Mountains. However, both the narrowly distributed S. bouffordiana and its more widespread close relative S. wardii are endemic and endangered. Furthermore, their small population sizes render each of these species at risk of extinction. To infer how past climate changes have shaped the evolutionary history of these species, we developed a chromosome-level S. bouffordiana genome (788&#x2009;Mb) and compared the two species' evolutionary histories, genetic loads and the genomic adaptions to local environmental conditions using whole-genome resequencing data. Our findings reveal a sharp population decline from the Pliocene to the Quaternary. However, populations of S. bouffordiana then started to recover before declining further, while S. wardii populations continued to decline until recently. Abundant homozygous-derived variants accumulated in the two species, particularly in S. bouffordiana, while the species with the most heterozygous variants was S. wardii. Accumulated extensive inbreeding effects but possessed few LOF mutations and few highly deleterious variants in the S. bouffordiana that have experienced the most severe demographic bottlenecks, most likely because of purging effects. This accelerating decline cascade will likely be detrimental to the consequences for the species' future viability and adaptive potential. Overall, this study improves our understanding of the evolutionary history of Salweenia shrubs tolerant to extreme environments and offers a genetic resource for future breeding and conservation efforts.

Genome, Plant

Two domesticated species of rice shaped the population structure of Xanthomonas oryzae pv. oryzae in Africa.

African rice (Oryza glaberrima) was independently domesticated in West Africa around 3000 years ago, and has long been intertwined in the history of the region. Asian rice (Oryza sativa), which was introduced in Africa when European settlers arrived, gradually replaced African rice and has since dominated rice cultivation in the continent. Domesticated rice species are affected by bacterial leaf blight (BLB), which is caused by the pathogen Xanthomonas oryzae pv. oryzae (Xoo). Here we show that the bacterial leaf blight pathogen in Africa (AfXoo) belongs to a distinct phylogroup from the one circulating in Asia (AsXoo), and has a different evolutionary history. Analysis of 87 AfXoo genomes identified five main populations, including highly clonal ones, and a more diverse and recombinant population. Tip-dating analysis revealed that the AfXoo population went through a period of expansion, then decline and more recent recovery. We hypothesize this followed the rise and fall of African rice, and that the introduction of O. sativa served as a bottleneck leading to the emergence of current AfXoo populations. We show that AfXoo has a highly conserved repertoire of type III effectors (T3E), but that nonetheless there is variation especially between populations. In the case of transcription activator-like effectors (TALEs), variation can arise quickly through rearrangements, and we hypothesize that the TALE repertoire of AfXoo has been selected to allow the bacteria to colonize both species of cultivated rice found in the continent. Our research provides an attempt to decipher the genetic history of bacterial blight in West Africa, and its past and present impact on rice cultivation in the region.

Journal Article

Doblin: inferring dominant clonal lineages from high-resolution DNA barcoding time series.

MOTIVATION: The lineage dynamics and history of cells in a population reflect the interplay of evolutionary forces they experience, including mutation, drift, and selection. When the population is polyclonal, lineage dynamics also manifest the extent of clonal competition among co-existing mutational variants. If the population exists in a community of other species, the lineage dynamics could also reflect the population's ecological interaction with the rest of the community. Recent advances in high-resolution lineage tracking via DNA barcoding, coupled with next-generation sequencing of bacteria, yeast, and mammalian cells, allow for precise quantification of clonal dynamics in these organisms. RESULTS: In this work, we introduce Doblin, an R suite for identifying dominant barcode lineages based on high-resolution lineage tracking data. We first benchmarked Doblin's accuracy using lineage data from evolutionary simulations, showing that it recovers the clones' identity and relative fitness in the simulation. Next, we applied Doblin to analyze clonal dynamics in laboratory evolutions of Escherichia coli populations undergoing antibiotic treatment and in colonization experiments of the gut microbial community. Doblin's versatility allows it to be applied to lineage time-series data across different experimental setups. AVAILABILITY AND IMPLEMENTATION: Doblin is available on CRAN (https://CRAN.R-project.org/package=doblin) and Github (https://github.com/dagagf/doblin).

DNA Barcoding, Taxonomic

Contrasting signals of selection at the EDAR gene in global and Latin American populations.

The EDAR gene is a classic target of positive selection in humans, mainly through the nonsynonymous variant rs3827760 (EDARV370A) associated with ectodermal traits. Using high-resolution data from the 1000 Genomes Project, we combined sliding-window F_ST, BayeScan, and extended haplotype homozygosity (EHH) analyses to examine global and Latin American patterns of differentiation. Globally, a strong signal of positive selection was confirmed at EDAR, dominated by the rs3827760 haplotype background and its extended linkage disequilibrium structure. In contrast, within Latin America, differentiation reflected admixture-driven haplotype persistence rather than contemporary selection. A genome-wide FST scan comparing individuals from the upper and lower quartiles of Native American ancestry showed that EDAR lies among the most highly differentiated regions in this contrast, consistent with ancestry-driven haplotype structure rather than post-admixture adaptive evolution. These results indicate that EDAR retains its evolutionary signature globally but not within recently admixed populations, where demographic history rather than selection shapes its genetic landscape.

Humans