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Sirenia, an iconic marine taxon with a tropical and subtropical worldwide distribution, face an uncertain future. All species are designated 'Vulnerable' to extinction by the IUCN. Nonetheless, a comprehensive understanding of geographic structuring across the global range is lacking, impeding our ability to highlight particularly vulnerable populations for conservation priority. Here, we use ancient DNA to investigate dugong (Dugong dugon) population structure, analysing 56 mitogenomes from specimens comprising the known historical range. Our results reveal geographically structured and distinct monophyletic clades characterized by contrasting evolutionary histories. We observe deep-rooted and divergent lineages in the East (Indo-Pacific) and obtain new evidence for the relatively recent dispersal of dugongs into the western Indian Ocean. All populations are significantly differentiated from each other with western populations having approximately 10-fold lower levels of genetic variation than eastern Indo-Pacific populations. Additionally, we find a significant temporal loss of genetic diversity in western Indian Ocean dugongs since the mid-twentieth century, as well as a decline in population size beginning approximately 1000 years ago. Our results add to the growing body of evidence that dugong populations are becoming ever more susceptible to ongoing human action and global climate change.
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Barley is one of the founder crops of the Neolithic transition in West Asia. While recent advances in genomics have provided a rather detailed picture of barley domestication, there are contradictory views on how the domestication process affected genetic diversity. We set out to revisit this question by integrating public DNA sequencing data from ancient barley and wide collections of extant wild and domesticated accessions. Using two previously overlooked approaches - analyses of chloroplast genomes and genome-wide proportions of private variants - we found that the barley cultivated six millennia ago was genetically unique and more diverse when compared to extant landraces and cultivars. Moreover, the chloroplast genomes revealed a link between the ancient barley, an obscure wild genotype from north-eastern Libya, and a distinct population of barley cultivated in Ethiopia/Eritrea. Based on these results, we hypothesize past existence of a wider North African population that included both wild and cultivated types and suffered from genetic erosion in the past six millennia, likely due to a rapid desertification that ended the Holocene African humid period. Besides providing clues about the origin of Ethiopian landraces, the hypothesis explains the post-domestication loss of diversity observed in barley. Analyses of additional samples will be necessary to resolve the history of African barley and its contribution to the extant cultivated gene pool.
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Connaraceae is a pantropical family of about 200 species containing lianas and small trees with remarkably diverse floral polymorphisms, including distyly, tristyly, homostyly, and dioecy. To date, relationships within the family have not been investigated using a targeted molecular phylogenetic treatment, severely limiting systematic understanding and reconstruction of trait evolution. Accordingly, their last infrafamilial classification was based only on morphological data. Here, we used phylogenomic data obtained using the Angiosperms353 nuclear target sequence capture probes, sampling all tribes and almost all genera, entirely from herbarium specimens, to revise infrafamilial classification and investigate the evolution of heterostyly. The backbone of the resulting molecular phylogenetic tree is almost entirely resolved. Connaraceae consists of two clades, one containing only the African genus Manotes (4 or 5 species), which we newly recognize at the subfamily level. Vegetative and reproductive synapomorphies are proposed for Manotoideae. Within Connaroideae, Connareae is expanded to include the former Jollydoreae. The backbone of Cnestideae, which contains more than half of the Connaraceae species, remains incompletely resolved. Reconstructions of reproductive system evolution are presented that tentatively support tristyly as the ancestral state for the family, with multiple parallel losses, in agreement with previous hypotheses, plus possible re-gains. However, the great diversity of stylar polymorphisms and their phylogenetic lability preclude a definitive answer. Overall, this study reinforces the usefulness of herbarium phylogenomics, and unlocks the reproductive diversity of Connaraceae as a model system for the evolution of complex biological phenomena. Supplementary Information: The online version contains supplementary material available at 10.1007/s00606-024-01909-y.
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The advent of genome-wide ancient DNA analysis has revolutionized our understanding of prehistoric societies. However, studying biological relatedness in these groups requires tailored approaches due to the challenges of analyzing ancient DNA. READv2, an optimized Python3 implementation of the most widely used tool for this purpose, addresses these challenges while surpassing its predecessor in speed and accuracy. For sufficient amounts of data, it can classify up to third-degree relatedness and differentiate between the two types of first-degree relatedness, full siblings and parent-offspring. READv2 enables user-friendly, efficient, and nuanced analysis of biological relatedness, facilitating a deeper understanding of past social structures.
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Arqueología , ADN Antiguo , Programas Informáticos , Humanos , ADN Antiguo/análisis , Arqueología/métodos , Genómica/métodos , LinajeRESUMEN
The petrous bone contains significantly higher amounts of DNA than any other human bone. Because of highly destructive sampling and because it is not always part of the recovered remains, the need for alternative sources of DNA is important. To identify additional optimal bone types, petrous bones were compared to femurs, tali, and calcanei sampled from 66 adult skeletons from two distinct modern-era Christian cemeteries. An extraction method employing full demineralization was used to obtain DNA, real-time PCR quantification to ascertain DNA quantity and degradation, and a commercial forensic short tandem repeats (STR) PCR amplification kit to determine genetic profiles. Statistical analysis was performed to explore the differences in DNA yield, DNA degradation, and success of STR amplification. A systematic studies exploring intra-skeletal variability in DNA preservation including various excavation sites differing by time period and geographical position are rare, and the second part of the investigation was based on a comparison of both archaeological sites, which allowed us to compare the effect of different post-mortem intervals and environmental conditions on DNA preservation. The older burial site in Crnomelj was active between the 13th and 18th century, whereas the more recent Polje burial was in use from the 16th to 19th century, creating different temporal and geographical environments. Results for the Crnomelj burial site revealed that the petrous bone outperformed all other bone types studied, except the calcaneus. At the Polje archeological site calcanei, tali, and femurs yielded the same STR typing success as petrous bones. The results obtained highlight the importance of careful bone sample selection for DNA analysis of aged skeletal remains. In addition to petrous bones, calcanei were found to be an alternative source of DNA when older burial sites are investigated. When more recent burial sites are processed, calcanei, tali, and femurs should be sampled besides petrous bones, not only because they exhibited good performance, but also because of easier sampling and easier grinding in the case of trabecular bones. This study contributes valuable insights into the potential use of various skeletal types as a source of DNA for investigation of aged skeletal remains, and it offers practical implications for forensic and archaeological investigations.
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Dermatoglifia del ADN , ADN , Repeticiones de Microsatélite , Reacción en Cadena en Tiempo Real de la Polimerasa , Humanos , Dermatoglifia del ADN/métodos , Masculino , ADN/análisis , ADN/aislamiento & purificación , Adulto , Persona de Mediana Edad , Femenino , Restos Mortales , Degradación Necrótica del ADN , Anciano , Fémur/química , Fémur/anatomía & histología , Historia Medieval , Huesos/química , Hueso Petroso/química , Hueso Petroso/anatomía & histología , Anciano de 80 o más Años , Antropología Forense/métodos , Adulto Joven , Calcáneo/anatomía & histologíaRESUMEN
The Yellow River Delta played a vital role in the development of the Neolithic civilization of China. However, the population history of this region from the Neolithic transitions to the present remains poorly understood due to the lack of ancient human genomes. This especially holds for key Neolithic transitions and tumultuous turnovers of dynastic history. Here, we report genome-wide data from 69 individuals dating to 5,410-1,345 years before present (BP) at 0.008 to 2.49× coverages, along with 325 present-day individuals collected from 16 cities across Shandong. During the Middle to Late Dawenkou period, we observed a significant influx of ancestry from Neolithic Yellow River farmers in central China and some southern Chinese ancestry that mixed with local hunter-gatherers in Shandong. The genetic heritage of the Shandong Longshan people was found to be most closely linked to the Dawenkou culture. During the Shang to Zhou Dynasties, there was evidence of genetic admixture of local Longshan populations with migrants from the Central Plain. After the Qin to Han Dynasties, the genetic composition of the region began to resemble that of modern Shandong populations. Our genetic findings suggest that the middle Yellow River Basin farmers played a role in shaping the genetic affinity of neighboring populations in northern China during the Middle to Late Neolithic period. Additionally, our findings indicate that the genetic diversity in the Shandong region during the Zhou Dynasty may be linked with their complex ethnicities.
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The medieval period in Sicily was turbulent, involving successive regime changes, from Byzantine (Greek Christian), Aghlabid (Sunni Muslim), Fatimid (Shi'a Muslim), to Normans and Swabians (Latin Christian). To shed new light on the local implications of regime changes, we conducted a multidisciplinary analysis of 27 individuals buried in adjacent Muslim and Christian cemeteries at the site of Segesta, western Sicily. By combining radiocarbon dating, genome-wide sequencing, stable and radiogenic isotopic data, and archaeological records, we uncover genetic differences between the two communities but find evidence of continuity in other aspects of life. Historical and archaeological evidence shows a Muslim community was present by the 12th century during Norman governance, with the Christian settlement appearing in the 13th century under Swabian governance. A Bayesian analysis of radiocarbon dates from the burials finds the abandonment of the Muslim cemetery likely occurred after the establishment of the Christian cemetery, indicating that individuals of both faiths were present in the area in the first half of the 13th century. The biomolecular results suggest the Christians remained genetically distinct from the Muslim community at Segesta while following a substantially similar diet. This study demonstrates that medieval regime changes had major impacts beyond the political core, leading to demographic changes while economic systems persisted and new social relationships emerged.
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Analyses of ancient DNA typically involve sequencing the surviving short oligonucleotides and aligning to genome assemblies from related, modern species. Here, we report that skin from a female woolly mammoth (Mammuthus primigenius) that died 52,000 years ago retained its ancient genome architecture. We use PaleoHi-C to map chromatin contacts and assemble its genome, yielding 28 chromosome-length scaffolds. Chromosome territories, compartments, loops, Barr bodies, and inactive X chromosome (Xi) superdomains persist. The active and inactive genome compartments in mammoth skin more closely resemble Asian elephant skin than other elephant tissues. Our analyses uncover new biology. Differences in compartmentalization reveal genes whose transcription was potentially altered in mammoths vs. elephants. Mammoth Xi has a tetradic architecture, not bipartite like human and mouse. We hypothesize that, shortly after this mammoth's death, the sample spontaneously freeze-dried in the Siberian cold, leading to a glass transition that preserved subfossils of ancient chromosomes at nanometer scale.
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Genoma , Mamuts , Piel , Animales , Mamuts/genética , Genoma/genética , Femenino , Elefantes/genética , Cromatina/genética , Fósiles , ADN Antiguo/análisis , Ratones , Humanos , Cromosoma X/genéticaRESUMEN
The hadopelagic environment remains highly understudied due to the inherent difficulties in sampling at these depths. The use of sediment environmental DNA (eDNA) can overcome some of these restrictions as settled and preserved DNA represent an archive of the biological communities. We use sediment eDNA to assess changes in the community within one of the world's most productive open-ocean ecosystems: the Atacama Trench. The ecosystems around the Atacama Trench have been intensively fished and are affected by climate oscillations, but the understanding of potential impacts on the marine community is limited. We sampled five sites using sediment cores at water depths from 2400 to ~8000 m. The chronologies of the sedimentary record were determined using 210Pbex. Environmental DNA was extracted from core slices and metabarcoding was used to identify the eukaryote community using two separate primer pairs for different sections of the 18S rRNA gene (V9 and V7) effectively targeting pelagic taxa. The reconstructed communities were similar among markers and mainly composed of chordates and members of the Chromista kingdom. Alpha diversity was estimated for all sites in intervals of 15 years (from 1842 to 2018), showing a severe drop in biodiversity from 1970 to 1985 that aligns with one of the strongest known El Niño events and extensive fishing efforts during the time. We find a direct impact of sea surface temperature on the community composition over time. Fish and cnidarian read abundance was examined separately to determine whether fishing had a direct impact, but no direct relation was found. These results demonstrate that sediment eDNA can be a valuable emerging tool providing insight in historical perspectives on ecosystem developments. This study constitutes an important step toward an improved understanding of the importance of environmental and anthropogenic drivers in affecting open and deep ocean communities.
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Biodiversidad , ADN Ambiental , Ecosistema , Sedimentos Geológicos , ARN Ribosómico 18S , Sedimentos Geológicos/análisis , ADN Ambiental/análisis , ARN Ribosómico 18S/genética , Chile , Animales , Código de Barras del ADN Taxonómico , Eucariontes/genética , Organismos Acuáticos/genéticaRESUMEN
Our knowledge of human evolutionary history has been greatly advanced by paleogenomics. Since the 2020s, the study of ancient DNA has increasingly focused on reconstructing the recent past. However, the accuracy of paleogenomic methods in resolving questions of historical and archaeological importance amidst the increased demographic complexity and decreased genetic differentiation remains an open question. We evaluated the performance and behavior of two commonly used methods, qpAdm and the f3-statistic, on admixture inference under a diversity of demographic models and data conditions. We performed two complementary simulation approaches - firstly exploring a wide demographic parameter space under four simple demographic models of varying complexities and configurations using branch-length data from two chromosomes - and secondly, we analyzed a model of Eurasian history composed of 59 populations using whole-genome data modified with ancient DNA conditions such as SNP ascertainment, data missingness, and pseudo-haploidization. We observe population differentiation is the primary factor driving qpAdm performance. Notably, whilst complex gene-flow histories influence which models are classified as plausible, they do not reduce overall performance. Under conditions reflective of the historical period, qpAdm most frequently identifies the true model as plausible amongst a small candidate set of closely related populations. To increase the utility for resolving fine-scaled hypotheses, we provide a heuristic for further distinguishing between candidate models that incorporates qpAdm model P-values and f3-statistics. Finally, we demonstrate a significant performance increase for qpAdm using whole-genome branch-length f2-statistics, highlighting the potential for improved demographic inference that could be achieved with future advancements in f-statistic estimations.
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We present palaeogenomes of three morphologically unidentified Anatolian equids dating to the first millennium BCE, sequenced to a coverage of 0.6-6.4×. Mitochondrial DNA haplotypes of the Anatolian individuals clustered with those of Equus hydruntinus (or Equus hemionus hydruntinus), the extinct European wild ass, secular name 'hydruntine'. Further, the Anatolian wild ass whole genome profiles fell outside the genomic diversity of other extant and past Asiatic wild ass (E. hemionus) lineages. These observations suggest that the three Anatolian wild asses represent hydruntines, making them the latest recorded survivors of this lineage, about a millennium later than the latest observations in the zooarchaeological record. Our mitogenomic and genomic analyses indicate that E. h. hydruntinus was a clade belonging to ancient and present-day E. hemionus lineages that radiated possibly between 0.6 and 0.8 Mya. We also find evidence consistent with recent gene flow between hydruntines and Middle Eastern wild asses. Analyses of genome-wide heterozygosity and runs of homozygosity suggest that the Anatolian wild ass population may have lost genetic diversity by the mid-first millennium BCE, a possible sign of its eventual demise.
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ADN Mitocondrial , Flujo Génico , Haplotipos , Filogenia , Animales , ADN Mitocondrial/genética , Haplotipos/genética , Equidae/genética , Genoma Mitocondrial , Extinción Biológica , Fósiles , Genética de Población , Variación GenéticaRESUMEN
Sedimentary ancient DNA (sedaDNA) has become one of the standard applications in the field of paleogenomics in recent years. It has been used for paleoenvironmental reconstructions, detecting the presence of prehistoric species in the absence of macro remains and even investigating the evolutionary history of a few species. However, its application in archaeology has been limited and primarily focused on humans. This article argues that sedaDNA holds significant potential in addressing key archaeological questions concerning the origins, lifestyles, and environments of past human populations. Our aim is to facilitate the integration of sedaDNA into the standard workflows in archaeology as a transformative tool, thereby unleashing its full potential for studying the human past. Ultimately, we not only underscore the challenges inherent in the sedaDNA field but also provide a research agenda for essential enhancements needed for implementing sedaDNA into the archaeological workflow.
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The Neolithic transition introduced major diet and lifestyle changes to human populations across continents. Beyond well-documented bioarcheological and genetic effects, whether these changes also had molecular-level epigenetic repercussions in past human populations has been an open question. In fact, methylation signatures can be inferred from UDG-treated ancient DNA through postmortem damage patterns, but with low signal-to-noise ratios; it is thus unclear whether published paleogenomes would provide the necessary resolution to discover systematic effects of lifestyle and diet shifts. To address this we compiled UDG-treated shotgun genomes of 13 pre-Neolithic hunter-gatherers (HGs) and 21 Neolithic farmers (NFs) individuals from West and North Eurasia, published by six different laboratories and with coverage c.1×-58× (median = 9×). We used epiPALEOMIX and a Monte Carlo normalization scheme to estimate methylation levels per genome. Our paleomethylome dataset showed expected genome-wide methylation patterns such as CpG island hypomethylation. However, analyzing the data using various approaches did not yield any systematic signals for subsistence type, genetic sex, or tissue effects. Comparing the HG-NF methylation differences in our dataset with methylation differences between hunter-gatherers versus farmers in modern-day Central Africa also did not yield consistent results. Meanwhile, paleomethylome profiles did cluster strongly by their laboratories of origin. Using larger data volumes, minimizing technical noise and/or using alternative protocols may be necessary for capturing subtle environment-related biological signals from paleomethylomes.
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China's Northern and Southern Dynasties period (3rd-6th centuries AD) marked a significant era of ethnic integration in northern China. However, previous ancient DNA studies have primarily focused on northern ethnic groups, with limited research on the genetic formation of the hereditary elite family, especially considering their abundant archaeological record and clear material identity. In this study, we obtained the ancient genome of a hereditary elite family, Gao Bin (, 503-572 AD), at 0.6473-fold coverage with 475132 single-nucleotide polymorphisms (SNPs) on the 1240k panel. His mitochondrial haplogroup belonged to Z4 and Y-haplogroup to O1a1a2b-F2444*. The genetic profile of Gao Bin was most similar to that of the northern Han Chinese. He could be modelled as deriving all his ancestry from Late Neolithic to Iron Age Yellow River farmers without influence from Northeast Asia, Korea, or the Mongolian Plateau. Our study sheds light on the genetic formation of hereditary elite families in the context of the Southern and Northern Dynasties ethnic integration.
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Shandong province, located in the Lower Yellow River, is one of the birthplaces of ancient Chinese civilization. However, the comprehensive genetic histories of this region have remained largely unknown until now due to a lack of ancient human genomes. Here, we present 21 ancient genomes from Shandong dating from the Warring States period to the Jin-Yuan Dynasties. Unlike the early Neolithic samples from Shandong, the historical samples are most closely related to post-Late Neolithic populations of the Middle Yellow River Basin, suggesting a population turnover in Shandong from the Neolithic Age to the Historical era. In addition, we detect a close genetic affinity between the historical samples in Shandong and present-day Han Chinese, showing long-term genetic stability in Han Chinese at least since the Warring States period.
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We here present CLUES2, a full-likelihood method to infer natural selection from sequence data that is an extension of the method CLUES. We make several substantial improvements to the CLUES method that greatly increases both its applicability and its speed. We add the ability to use ancestral recombination graphs on ancient data as emissions to the underlying hidden Markov model, which enables CLUES2 to use both temporal and linkage information to make estimates of selection coefficients. We also fully implement the ability to estimate distinct selection coefficients in different epochs, which allows for the analysis of changes in selective pressures through time, as well as selection with dominance. In addition, we greatly increase the computational efficiency of CLUES2 over CLUES using several approximations to the forward-backward algorithms and develop a new way to reconstruct historic allele frequencies by integrating over the uncertainty in the estimation of the selection coefficients. We illustrate the accuracy of CLUES2 through extensive simulations and validate the importance sampling framework for integrating over the uncertainty in the inference of gene trees. We also show that CLUES2 is well-calibrated by showing that under the null hypothesis, the distribution of log-likelihood ratios follows a χ2 distribution with the appropriate degrees of freedom. We run CLUES2 on a set of recently published ancient human data from Western Eurasia and test for evidence of changing selection coefficients through time. We find significant evidence of changing selective pressures in several genes correlated with the introduction of agriculture to Europe and the ensuing dietary and demographic shifts of that time. In particular, our analysis supports previous hypotheses of strong selection on lactase persistence during periods of ancient famines and attenuated selection in more modern periods.
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ADN Antiguo , Frecuencia de los Genes , Modelos Genéticos , Selección Genética , Humanos , ADN Antiguo/análisis , Funciones de Verosimilitud , Cadenas de Markov , Algoritmos , Evolución Molecular , Alelos , Simulación por ComputadorRESUMEN
Dingoes are culturally and ecologically important free-living canids whose ancestors arrived in Australia over 3,000 B.P., likely transported by seafaring people. However, the early history of dingoes in Australia-including the number of founding populations and their routes of introduction-remains uncertain. This uncertainty arises partly from the complex and poorly understood relationship between modern dingoes and New Guinea singing dogs, and suspicions that post-Colonial hybridization has introduced recent domestic dog ancestry into the genomes of many wild dingo populations. In this study, we analyzed genome-wide data from nine ancient dingo specimens ranging in age from 400 to 2,746 y old, predating the introduction of domestic dogs to Australia by European colonists. We uncovered evidence that the continent-wide population structure observed in modern dingo populations had already emerged several thousand years ago. We also detected excess allele sharing between New Guinea singing dogs and ancient dingoes from coastal New South Wales (NSW) compared to ancient dingoes from southern Australia, irrespective of any post-Colonial hybrid ancestry in the genomes of modern individuals. Our results are consistent with several demographic scenarios, including a scenario where the ancestry of dingoes from the east coast of Australia results from at least two waves of migration from source populations with varying affinities to New Guinea singing dogs. We also contribute to the growing body of evidence that modern dingoes derive little genomic ancestry from post-Colonial hybridization with other domestic dog lineages, instead descending primarily from ancient canids introduced to Sahul thousands of years ago.
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Genoma , Animales , Australia , Perros/genética , Lobos/genética , ADN Antiguo/análisis , Genética de PoblaciónRESUMEN
The combination of multi-omic techniques, such as genomics, transcriptomics, proteomics, metabolomics and epigenomics, has revolutionised studies in medical research. These techniques are employed to support biomarker discovery, better understand molecular pathways and identify novel drug targets. Despite concerted efforts in integrating omic datasets, there is an absence of protocols that integrate all four biomolecules in a single extraction process. Here, we demonstrate for the first time a minimally destructive integrated protocol for the simultaneous extraction of artificially degraded DNA, proteins, lipids and metabolites from pig brain samples. We used an MTBE-based approach to separate lipids and metabolites, followed by subsequent isolation of DNA and proteins. We have validated this protocol against standalone extraction protocols and show comparable or higher yields of all four biomolecules. This integrated protocol is key to facilitating the preservation of irreplaceable samples while promoting downstream analyses and successful data integration by removing bias from univariate dataset noise and varied distribution characteristics.
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Multiómica , Animales , Encéfalo/metabolismo , ADN/aislamiento & purificación , Genómica/métodos , Lípidos/análisis , Metabolómica/métodos , Multiómica/métodos , Proteínas/aislamiento & purificación , Proteínas/metabolismo , Proteómica/métodos , PorcinosRESUMEN
Facial morphology, a complex trait influenced by genetics, holds great significance in evolutionary research. However, due to limited fossil evidence, the facial characteristics of Neanderthals and Denisovans have remained largely unknown. In this study, we conducted a large-scale multi-ethnic meta-analysis of the genome-wide association study (GWAS), including 9674 East Asians and 10,115 Europeans, quantitatively assessing 78 facial traits using 3D facial images. We identified 71 genomic loci associated with facial features, including 21 novel loci. We developed a facial polygenic score (FPS) that enables the prediction of facial features based on genetic information. Interestingly, the distribution of FPSs among populations from diverse continental groups exhibited relevant correlations with observed facial features. Furthermore, we applied the FPS to predict the facial traits of seven Neanderthals and one Denisovan using ancient DNA and aligned predictions with the fossil records. Our results suggested that Neanderthals and Denisovans likely shared similar facial features, such as a wider but shorter nose and a wider endocanthion distance. The decreased mouth width was characterized specifically in Denisovans. The integration of genomic data and facial trait analysis provides valuable insights into the evolutionary history and adaptive changes in human facial morphology.
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OBJECTIVE: Here we investigate infectious diseases that potentially contribute to osteological lesions in individuals from the early medieval necropolis of La Olmeda (6th-11th c. CE) in North Iberia. MATERIALS AND METHODS: We studied a minimum number of 268 individuals (33 adult females; 38 adult males, 77 unknown/indeterminate sex; and 120 non-adults), including articulated and commingled remains. Individuals with differential diagnoses suggesting chronic systemic infectious diseases were sampled and bioinformatically screened for ancient pathogen DNA. RESULTS: Five non-adults (and no adults) presented skeletal evidence of chronic systemic infectious disease (1.87% of the population; 4.67% of non-adults). The preferred diagnoses for these individuals included tuberculosis, brucellosis, and malaria. Ancient DNA fragments assigned to the malaria-causing pathogen, Plasmodium spp., were identified in three of the five individuals. Observed pathology includes lesions generally consistent with malaria; however, additional lesions in two of the individuals may represent hitherto unknown variation in the skeletal manifestation of this disease or co-infection with tuberculosis or brucellosis. Additionally, spondylolysis was observed in one individual with skeletal lesions suggestive of infectious disease. CONCLUSIONS: This study sheds light on the pathological landscape in Iberia during a time of great social, demographic, and environmental change. Genetic evidence challenges the hypothesis that malaria was absent from early medieval Iberia and demonstrates the value of combining osteological and archaeogenetic methods. Additionally, all of the preferred infectious diagnoses for the individuals included in this study (malaria, tuberculosis, and brucellosis) could have contributed to the febrile cases described in historical sources from this time.