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Daly, K. G.

Publications and source records attributed to Daly, K. G..

12 recordsLinked to original sources

PIGSTI: a modular, reproducible pipeline for detecting species identity, pathogens, and microbes from animal palaeogenomic data

Ancient genomics has enabled discovery of diverse pathogens across various time periods, host species, and material types. However, existing palaeogenomic pipelines predominantly focus on screening data from human hosts, or do not incorporate microbial screening methodologies. We present PIGSTI (Pathogen anImal Genome Sequence ToolkIt), a bioinformatic pipeline specifically designed for both the initial screening and subsequent detection of pathogens in shotgun sequencing data from ancient animal remains. PIGSTI's integrated Snakemake workflow performs both host detection, genome mapping and pathogen identification, generating outputs suitable for population genetics and phylogenetic analyses. Testing on 952 newly sequenced and publicly available animal palaeogenomic datasets, we identified ~15 ancient zoonotic and animal pathogens with high confidence, including the first documented case of Rickettsia felis and Leptospira borgpetersenii in an ancient animal. Our results demonstrate PIGSTI's utility for screening pathogen diversity in ancient animal hosts and reconstructing historical host-pathogen relationships.

genomics↗

A multi-tissue epigenomic atlas links the sheep non-coding genome to domestication and complex traits

Non-coding regulatory variation drives complex traits, domestication, and evolutionary adaptation, yet the sheep genome lacks high-resolution functional annotation. Here we present SheepEpimap, a multi-tissue regulatory atlas harmonizing 516 CUT&Tag histone modifications, ATAC-seq, and RNA-seq datasets across 43 adult tissues in sheep. We annotated 2.93 million cis-regulatory elements, yielding 557,441 enhancer-gene pairs and 145,407 variants with allele-specific effects. By training a sequence-to-function deep-learning model, we decoded the base-pair syntax of chromatin accessibility, annotated transcription factor motif instances genome-wide, and constructed 12,210 tissue-specific gene regulatory networks (GRNs). Integrating this resource with multi-tissue expression quantitative trait loci, selection sweeps, and genome-wide association studies prioritized non-coding variants driving domestication and complex traits. Finally, cross-species analysis revealed that sequence-conserved, tissue-matched enhancers were significantly enriched in the heritability of complex traits and diseases in humans. In summary, SheepEpimap (https://genome.ucsc.edu/s/mengzhu/SheepEpimap) provides an open-access foundational ecosystem for sheep functional genomics, precision breeding, and comparative biology.

genetics↗

Mediterranean dispersal imposed bottlenecks in Neolithic sheep and goats

The Neolithic period in western Eurasia involved major dispersal events, including the translocation of livestock into Europe. These domestic animal translocations likely featured founder effects, fundamentally reshaping their genetic landscape. One well-known example is the Mediterranean dispersal, hypothesised to involve rapid maritime translocation with small founding herds, yet the genetic consequences for the livestock themselves remain poorly understood. To investigate this, we generated 12 palaeogenomes of sheep and goat from La Draga and Cova de lAvellaner, and coanalyzed these with other Neolithic Mediterranean assemblages, including 4 additional novel genomes. We observe a significantly lower genetic diversity and higher runs of homozygosity (ROH) in Iberian sheep and goat populations compared to other ancient European and southwest Asian populations. We quantify the magnitude of the bottleneck in goats at [~]205 Ne, highlighting the severity of the founder event. We further identify species-specific demographic trajectories: goats experienced a severe and prolonged bottleneck, likely driven by regional isolation within the western Mediterranean, intensive exploitation strategies, and small initial founding herds, while sheep were likely more frequently exchanged across the region. Lastly, identity-by-descent (IBD) indicates connectivity along the Mediterranean coast compatible with a cabotage model. This suggests that seaways facilitated rapid initial dispersal but not sustained livestock transfer from southwest Asia, shaping the genetic foundation of Iberian livestock herds. SignificanceThe Neolithic transition in western Eurasia fundamentally restructured human societies, yet the genetic consequences for translocated livestock remain poorly characterized. Analyzing 16 novel palaeogenomes from Mediterranean Neolithic sheep and goats, we demonstrate that maritime dispersal imposed severe founder effects on early Iberian livestock, reducing effective population sizes to as low as [~]205 in goats. Species-specific demographic trajectories reveal that goats experienced prolonged genetic isolation within the western Mediterranean, while sheep maintained broader regional connectivity. Identity-by-descent analyses support a cabotage model of coastal dispersal, indicating that Mediterranean seaways facilitated rapid initial colonization but not sustained genetic exchange with southwest Asian source populations. These findings reveal that the earliest livestock introductions into Europe were demographically constrained events whose genetic signatures persist in the foundations of Iberian pastoral heritage.

genomics↗

Evolutionary history and genomic vulnerability of the extinct giant deer Megaloceros giganteus

The extinct giant deer (Megaloceros giganteus) was one of the most striking megafaunal species of the Late Quaternary, distinguished by its enormous palmated antlers reaching up to 3.5 m across, the largest known among both living and extinct cervids. Despite its iconic status, little is known about its genomic history prior to extinction [~]8 thousand years ago (kya). We generated the first nuclear palaeogenomes for Megaloceros, represented by nine individuals from Germany ([~]40 kya) and Ireland ([~]11 kya), mapped to a new chromosome-level reference genome of the fallow deer (Dama dama). Phylogenomic analyses placed Megaloceros as sister to Dama (divergence [~]3.5 Ma) and revealed evidence of gene flow with ancestral Cervus lineages. Population analyses identified clear differentiation between German and Irish lineages, with higher genetic diversity in the German individuals. Two genes under strong positive selection, BNIPL and SLC10A7, are associated with apoptosis regulation and skeletal development/bone mineralisation, respectively, and may relate to the species large body and antler size. Demographic reconstructions indicate a long-term decline in effective population size, extremely low heterozygosity, little evidence of extensive runs of homozygosity, and an elevated burden of predicted deleterious alleles. Together, these results suggest that Megaloceros entered the terminal Pleistocene in a genomically fragile state, offering new insight into the biology and evolutionary legacy of one of the largest and most distinctive cervids that ever lived.

evolutionary biology↗

3,500 years of sheeppox virus evolution inferred from archaeological and codicological genomes

Sheeppox virus (SPPV) is a major livestock pathogen causing economic hardship through reduced production and death of vulnerable sheep, with written descriptions of sheeppox-like disease recorded since antiquity. We report 21 novel ancient SPPV genomes spanning the Eurasian steppe Bronze Age ([~]1,700 BCE) to the Early Modern period in Western Europe, including multiple genomes obtained from medieval parchment. We estimate that major capripoxvirus lineages diverged [~]11,500-3,700 years ago, overlapping known translocations and bio-cultural developments in sheep. Our dataset supports SPPV diverging first within the lineage leading to goatpox virus and lumpy skin disease virus, and that known gene inactivation events within SPPV and goatpox virus occur in our earliest SPPV genomes. These findings reveal that the food security of Eurasian communities have been threatened by sheeppox for over 3,700 years, and provide new insights to the genomic evolution and potential host adaptation of sheeppox virus. TeaserAncient viral genomes from manuscripts and teeth illuminate the evolutionary history of sheeppox virus.

genetics↗

Genetic analysis of 7,000 year old preserved goat leather from Cueva de los Murcielagos (Albunol, Spain).

Advances in ancient DNA research have expanded the range of materials from which genetic information can be recovered, enabling the analysis of atypical materials. These often preserve both host and exogenous DNA, for example due to handling or native microbes, offering a window into past diversity. Here we report one such exceptional material: a well-preserved goat leather specimen from Cueva de los Murcielagos (Albunol, Spain), associated with an Early Neolithic context. Archaeozoological analyses show clear evidence of tanning and anthropogenic modification of the skin, while radiocarbon dating confirms it to be [~]7,250-7,000 years old. We generated genome-wide data from the leather (Murcielagos1) and demonstrated that it derives from a domestic goat of European ancestry. Comparisons with modern goats show highest affinity to the Bermeya breed from northern Spain, demonstrating genetic connectivity in goat herds from the Neolithic to present day Iberia. We additionally recover fragmented DNA from the leather deriving from human and canid sources, the former likely reflecting handling/wearing of the leather and the latter indicating post-depositional disturbance. Murcielagos1 represents one of the oldest nuclear genome data from organic remains outside of high altitude, high latitude regions, and demonstrates the value of ancient DNA analysis in exceptional cases of organic preservation.

genomics↗

Evidence of sheeppox in 17th-19th century France: a multi-disciplinary investigation of a sheep mass mortality assemblage

Epizootic outbreaks posed major threats to food security, economic stability, and animal welfare in past communities. While these events and their impacts are well documented in historical records, very few archaeological examples are known, and none for which the causal agent has been reliably identified. We therefore investigated a 17 th-19th century ovine mass-mortality assemblage from Louvres, France, using an interdisciplinary approach integrating paleogenetics, zooarchaeology, history, and veterinary science. The deposit contained nine complete, articulated sheep skeletons, mostly older individuals of both sexes, which were unbutchered but displayed flaying marks. Aside from minor age-related lesions and one ectopic bone nodule, the animals exhibited good skeletal health, with no obvious cause of death. Ancient DNA analysis was therefore conducted and proved highly successful, conclusively identifying two ovine pathogens: sheeppox virus (SPPV) and the parasite Taenia hydatigena. When considered alongside archaeological, veterinary and historical evidence, these findings indicate that the animals died during a sheeppox outbreak. This study provides the first detection of SPPV in archaeological bone and the first paleogenome of this virus. It also offers new insights into livestock health, mortality, and disease management in early modern France, demonstrating the value of integrated approaches for reconstructing past epizootics.

genetics↗

Old Goats: 3,000 years of genetic connectivity of the domestic goat in Ireland

The domestic goat likely first arrived to the island of Ireland as part of the introduction of agriculture approximately 5,900 years ago, and remains a part of the islands biocultural heritage. However, due to the challenges of differentiating goat remains from that of sheep using traditional archaeozoological approaches, there are few specimens specifically identified as goat. To address this we employed genetic, proteomics, and archaeozoological techniques to assess faunal remains from the Late Bronze assemblage of Haugheys Fort (Armagh) and medieval assemblage of Carrickfergus (Antrim). We identify these specimens as goats using proteomics and genetics, and additionally determine their molecular sex. Genomic data recovered from a Haugheys Fort goat reveals a three-millenia genetic connection between herds in the Late Bronze Age, medieval period, and the indigenous Irish breed extant today, the Old Irish Goat. We additionally find varying levels of inbreeding within goats from the settlement of Carrickfergus, suggesting possible mixed use of herds within medieval Irish society. Our results demonstrate the continuing potential of combining archaeological and biomolecular techniques to clarify existing ambiguities and at the same time reveal new facets of the past.

genomics↗

Inferring domestic goat demographic history through ancient genome imputation

Goats were among the earliest managed animals, making them a natural model to explore the genetic consequences of domestication. However, a challenge in ancient genomic analysis is the relatively low genome coverage for most samples, limiting analysis to pseudohaploid genotypes. Genotype imputation offers potential to alleviate this limitation by improving information content and accuracy in low coverage genomes. To test this we used published high coverage (>8x) goat palaeogenomes, imputing downsampled genomes using the VarGoats dataset (1,372 individuals) as a reference panel. Measuring concordance between imputed and high coverage genotypes, we find high concordance after filtering for common (>5%), high confidence variants, with 0.5x genomes reaching >0.97 concordance. There is a trade-off between coverage, genotype probability (GP) thresholds, and genotype recovery, where higher coverage and more lenient GP thresholds result in higher recovery, and a reduction in heterozygous false-positive rates with stricter thresholds. We then imputed 36 goat palaeogenomes with [≥]0.5x coverage to examine runs-of-homozygosity (ROH) and identity-by-descent (IBD) patterns. Using a novel approach combining ROH profiles across tools, we find that among Neolithic goats, ROH increases with distance from the Zagros Mountains, suggesting a large effect of the initial dispersal of managed herds. Inbreeding levels decrease across Southwest Asia in more recent periods. IBD mirrored this pattern, with less relatedness in the early herding site of Ganj Dareh compared to higher relatedness in goats from later in the dispersal process. These findings provide insights into the genetic consequences of early goat management on demography, and confirm the utility of imputation in leveraging low coverage palaeogenomes. SignificancePaleogenomics offers crucial insight into how animals were domesticated, but poor DNA preservation in ancient remains often limits the reach of genetic analyses. We utilise a cutting-edge technique, genotype imputation, to recover missing genetic information from ancient low coverage goat genomes and shine light on their domestication process. Early domestic goats showed low overall runs-of-homozygosity (ROH) and relatedness. We find that during the Neolithic, runs-of-homozygosity (ROH) and relatedness among goats increased, likely a consequence of the movement of herds beyond their natural range by humans. Inbreeding levels decline in more recent periods, potentially due to expanded herd sizes, animal trade networks, or improved husbandry practices. These findings challenge long-standing assumptions about domestication bottlenecks and highlight how ancient DNA can be used to uncover complex evolutionary histories, even from low coverage ancient samples.

genomics↗

A novel lineage of the Capra genus discovered in the Taurus Mountains of Turkey using ancient genomics.

AO_SCPLOWBSTRACTC_SCPLOWDirekli Cave, located in the Taurus Mountains of southern Turkey, was occupied by Late Epipaleolithic hunters-gatherers for the seasonal hunting and processing of game including large numbers of wild goats. We report genomic data from new and published Capra specimens from Direkli Cave and, supplemented with historic genomes from multiple Capra species, find a novel lineage best represented by a [~]14,000 year old 2.59X genome sequenced from specimen Direkli4. This newly discovered Capra lineage is a sister clade to the Caucasian tur species (Capra cylindricornis and Capra caucasica), both now limited to the Caucasus region. We identify genomic regions introgressed in domestic goats with high affinity to Direkli4, and find that West Eurasian domestic goats in the past, but not those today, appear enriched for Direkli4-specific alleles at a genome-wide level. This forgotten "Taurasian tur" likely survived Late Pleistocene climatic change in a Taurus Mountain refugia and its genomic fate is unknown.

genomics↗

Exceptional ancient DNA preservation and fibre remains of a Sasanian saltmine sheep mummy in Chehrabad, Iran

Mummified remains have long attracted interest as a potential source of ancient DNA. However, mummification is a rare process that requires an anhydrous environment to rapidly dehydrate and preserve tissue before complete decomposition occurs. We present the whole genome sequences of a [~]1600 year old naturally mummified sheep recovered from Chehr[a]b[a]d, a salt mine in northwestern Iran. Comparative analyses of published ancient sequences revealed remarkable DNA integrity of this mummy. Hallmarks of postmortem damage, fragmentation and hydrolytic deamination, are substantially reduced, likely due to the high-salinity of this taphonomic environment. Metagenomic analyses reflect the profound influence of high salt content on decomposition; its microbial profile is predominated by halophilic archaea and bacteria, possibly contributing to the preservation of this sample. Applying population genomic analyses we find consistent clustering of this sheep with Southwest Asian modern breeds, suggesting ancestry continuity. Genotyping of a locus influencing the woolly phenotype showed the existence of an ancestral "hairy" allele in this sheep, consistent with hair fibre imaging, further elucidating Sasanian-period animal husbandry.

genomics↗

Phylogeny and distribution of Y-chromosomal haplotypes in domestic, ancient and wild goats

The male-specific part of the Y-chromosome is in mammalian and many other species the longest haplotype that is inherited without recombination. By its paternal transmission it has a small effective population size in species with dominant males. In several species, Y-chromosomal haplotypes are sensitive markers of population history and introgression. Previous studies have identified in domestic goats four major Y-chromosomal haplotypes Y1A, Y1B, Y2A and Y2B with a marked geographic differentiation and several regional variants. In this study we used published whole-genome sequences of 70 male goats from 16 modern breeds, 11 ancient-DNA samples and 29 samples from seven wild goat species. We identified single-copy male-specific SNPs in four scaffolds, containing SRY, ZFY, DBY with SSX3Y and UTY, and USP9Y with UMN2001, respectively. Phylogenetic analyses indicated haplogroups corresponding to the haplotypes Y1B, Y2A and Y2B, respectively, but Y1A was split into Y1AA and Y1AB. All haplogroups were detected in ancient DNA samples from southeast Europe and, with the exception of Y1AB, in the bezoar goat, which is the wild ancestor of the domestic goats. Combining these data with those of previous studies and with genotypes obtained by Sanger sequencing or the KASP assay yielded haplogroup distributions for 132 domestic breeds or populations. The phylogeographic differentiation indicated paternal population bottlenecks on all three continents. This possibly occurred during the Neolithic introductions of domestic goats to those continents with a particularly strong influence in Europe along the Danubian route. This study illustrates the power of the Y-chromosomal haplotype for the reconstructing the history of mammalian species with a wide geographic range.

genetics↗