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Rosen, B. D.

Publications and source records attributed to Rosen, B. D..

17 recordsLinked to original sources

Linking geography and mutation profiles across goat species

Recent studies have characterised the mutational profile across multiple mammalian species, highlighting substantial differences across lineages. However, none of these studies investigated whether mutation profiles and geography are significantly correlated. In this study, we present a multi-genome alignment spanning several Capra taxa, reconstruct the ancestral genome of Capra hircus and use it to characterize the mutational profiles across multiple Capra species by using the 1000 genomes VarGoats dataset. Results confirmed that the scale of differences among Capra species largely reflects their phylogenetic relationships, in particular with the Bezoar being genetically closer to domestic goats than to other wild species. Subsequently, we correlated the mutational profile and the geographical origin of the different individuals. In particular, ACG>ATG changes have the strongest correlation with longitude (r = -0.79, P-value = 3.02*10-204), while TCA>TGA are strongly correlated with latitude (r = -0.51, P-value = 4.30*10-63). We highlight how sequential dinucleotide mutations (SDMs) place cosmopolitan breeds closer to the sampling location, rather than the country of origin, showing how the recent relocation of cosmopolitan breeds to new continents is reshaping the genome of these animals. Finally, we used the mutational profile to predict the coordinate of origin of each animal in the dataset. In conclusion, we show the important role that geography had in shaping the genomes of domestic goats.

genomics↗

Bighorn sheep T2T genome assembly reveals differences in immune genes: a potential cause of high morbidity due to respiratory pathogens

The bighorn sheep (Ovis canadensis), despite its close relation to domestic sheep, suffer higher morbidity and mortality from respiratory disease complexes, likely due to genetic differences in immune responses. Unraveling highly repetitive regions such as immune loci and genetic differences was problematic until now. We generated a bighorn sheep telomere-to-telomere assembly, adding 14.28% of novel sequence compared to the previous reference. This enabled the first complete immune loci annotation revealing the IGL and TR loci are significantly short in bighorn sheep. Importantly, a critical immune gene GBP5 and ZNF501, involved in Golgi-mediated immune response, are lacking in bighorn but present in domestic sheep. Re-analysis of a Mycoplasma ovipneumoniae carriage study, using this assembly, identified the immune gene CAPN2 as a key genetic marker for disease carriage, not observable in the original study. This work provides a critical resource for identifying phenotype-linked genetic variation and exploring evolutionary adaptations of bighorn sheep.

genomics↗

Finishing a complete giraffe genome from telomere to telomere with Verkko-Fillet

High-quality genome assemblies are essential for understanding speciation, evolution, and for building reference genomes and pan-genomes. Despite major advances in long-read sequencing technologies and graph-based assembly algorithms, current assemblies often remain incomplete and require refinement, including correction of haplotype switching and resolution of gaps, particularly within repetitive regions such as ribosomal DNA clusters and recent segmental duplications. These limitations largely stem from challenges in graph curation and are not adequately addressed by conventional polishing methods, which focus primarily on nucleotide-level corrections. To overcome these issues, we developed Verkko-Fillet, a Python-based interactive framework for genome graph inspection, editing, and curation that also provides step-by-step guidelines for downstream polishing. Verkko-Fillet takes as input Verkko output files, including the assembly graph, haplotype paths, Hi-C contacts, and additional ONT reads or alternative assemblies aligned to the graph, and offers tools for visualizing, modifying, and exporting curated assembly graphs. It enables users to track changes, resolve complex structural features, fill gaps, and enhance assembly quality beyond conventional polishing. As a case study, we applied Verkko-Fillet to the giraffe genome (Giraffa tippelskirchi), refining a draft assembly (QV 61.5) to a telomere-to-telomere (T2T) reference genome (QV 73.6) by improving both contiguity and completeness. Along with the T2T diploid giraffe genome, we provide gene annotations on this assembly as a valuable resource. Our results highlight the critical role of graph-based curation in producing high-quality, gapless, T2T assemblies that are ready for downstream biological analyses.

bioinformatics↗

Population structure and domestication history of the Javan banteng (Bos javanicus javanicus)

The domestication of the banteng in Southeast Asia is one of the Worlds least known livestock domestications, yet a vital component of the agricultural system in Indonesia and surrounding countries. Here we generated the first reference genome of the banteng and used it to analyze a set of 78 resequenced wild and domesticated bantengs, including 19 newly generated whole-genome sequenced samples of which three are historical samples. We found low heterozygosity and significant differentiation, the latter primarily driven by recent genetic drift and inbreeding in two populations, and clearly attributable to anthropogenically driven founder events or ex-situ breeding. Population structure when excluding these two populations was limited, and we found that the evolutionary divergence between wild and domestic banteng is moderate (FST = 0.14), relatively young (10,356 years), and with post-divergence gene flow. We found only weak signals of a domestication bottleneck between [~]6100-2900 years ago, and genetic diversity is on average higher in domestic than in wild banteng. Despite the soft domestication history, we found 56 candidate genes under selection during domestication, with the leptin receptor gene (LEPR) of particular interest due to the robust selection signal across methods, and its known association to metabolism, obesity and energy homeostasis. Finally, genetic load estimation revealed that Bali cattle in Australia have high realized load, while Bali cattle from Bali have high masked load. These findings provide the first genomic insights into an understudied bovine that is Critically Endangered in its wild form, and agriculturally important in its domesticated form.

evolutionary biology↗

Genome assemblies of Indian desi cattle reveals hotspots of rearrangements and immune-related genetic diversity

India, home to the worlds largest cattle population, hosts native dairy breeds essential to its agricultural economy because of their adaptability and resilience. This study characterizes the genomes of five prominent breeds Gir, Kankrej, Red Sindhi, Sahiwal and Tharparkar, highlighting their unique genomic characteristics. The de novo assemblies ranged from 2.70-2.78 Gb in size, with 90% of the genomes assembled in just 56 to 1,663 scaffolds. The use of reference-guided scaffolding further enhanced these genomes, resulting in 93.3-96.7% pseudomolecule coverage with strong BUSCO scores (94.1-95.5%). Comparative analyses revealed 87-95% synteny with the Brahman genome and identified 19.84-153.16 Mb of structural rearrangements per genome, including inversions, translocations, and duplications. Synteny diversity analysis uncovered 10,643 perfectly collinear regions spanning 87.3 Mb and 6,622 hotspots of rearrangement (HOT regions) covering 55.18 Mb. These HOT regions, characterized by high synteny diversity, were significantly enriched with immune-related genes. Moreover, immune-related gene clusters, including MHC, NKC, and LRC, were identified within HOT regions in the desi reference genome. Our findings provide valuable insights into the genetic diversity of desi cattle breeds. The high-quality genome assemblies generated in this study will serve as valuable resources for future research in genetic improvement, disease resistance, and environmental adaptation.

genomics↗

Constructing a Draft Indian Cattle Pangenome Using Short-Read Sequencing

BackgroundIndian cattle known as desi cattle, renowned for their adaptability to harsh environments and diverse phenotypic traits, represent a valuable genetic resource. While reference genome assemblies have been instrumental in advancing cattle genomics, they often fail to capture the full spectrum of genetic variation present within diverse populations. To address this limitation, we aimed to construct a pangenome for desi cattle by identifying and characterizing Non-Reference Novel Sequences (NRNS). FindingsWe sequenced 68 desi cattle genomes representing seven distinct breeds, generating 48.35 billion short reads. A PanGenome Analysis (PanGA) pipeline was developed in Bash scripts to process these data to identify NRNS missing in the reference genome. A total of 13,065 NRNS with a cumulative length of [~]41 Mbp were identified that exhibited substantial variation across the population. These NRNS were found to be exclusive to Indian desi cattle, matching only 4.1% with the Chinese indicine pangenome. However, a significant proportion ([~]40%) of NRNS displayed ancestral origins within the Bos genus. These sequences were enriched in genic regions, suggesting functional roles, and were associated with quantitative trait loci (QTLs), particularly for milk production. Compared to a single reference genome, the pangenome approach significantly enhanced read mapping accuracy, reduced spurious SNP calls, and facilitated the discovery of novel genetic variants. ConclusionsThis study has successfully established a within-species cattle pangenome specifically focused on desi cattle breeds from India. Our findings highlight the importance of pangenome based analyses for understanding the complex genetic architecture of desi cattle.

genomics↗

Advancing the Indian Cattle Pangenome: Characterizing Non-Reference Sequences in Bos indicus

BackgroundIndia, with the worlds largest cattle population and more than 50 registered breeds of Bos indicus, stands as a vital reservoir of genetic diversity. However, the abundant diversity among Indian cattle breeds highlights the inadequacy of a single reference sequence to represent the entire genomic content of desi cattle. We recognize the need to capture the genomic differences within the Bos indicus population as a whole, and specifically within the dairy cattle subset by identifying non-reference sequences and constructing a pangenome. FindingFive representative genomes of prominent dairy breeds, including Gir, Kankrej, Tharparkar, Sahiwal, and Red Sindhi, were sequenced using 10X Genomics Linked-Read technology. Assemblies generated from these linked-reads ranged from 2.70 Gb to 2.77 Gb,comparable to the Bos indicus Brahman reference genome. A pangenome of Bos indicus cattle was constructed by comparing the newly assembled genomes with the reference using alignment and graph-based methods, revealing 8 Mb and 17.7 Mb of novel sequence respectively. A confident set of 6,844 Non-Reference Unique Insertions (NUIs) spanning 7.57 Mbs was identified through both methods, representing the pangenome of Indian Bos indicus breeds. Comparative analysis with previously published pangenomes unveiled 2.8 Mb (37%) commonality with the Chinese indicine pangenome and only 1% commonality with the Bos taurus pangenome. Among these, 2,312 NUIs - encompassing [~]2 Mb, were commonly found in 98 samples of the 5 breeds and designated as Bos indicus Common Insertions (BICIs) in the population. Furthermore, 926 BICIs were identified within 682 protein-coding genes, 54 long non-coding RNAs (LncRNA), and 18 pseudogenes. These protein-coding genes were enriched for functions such as chemical synaptic transmission, cell junction organization, cell-cell adhesion, and cell morphogenesis. The protein-coding genes were found in various prominent Quantitative Trait Loci (QTL) regions, suggesting potential roles of BICIs in traits related to milk production, reproduction, exterior, health, meat, and carcass. Notably, 63.21% of the bases within the BICIs call set contained interspersed repeats, predominantly LINEs. Additionally,70.28% of BICIs are shared with other domesticated and wild species, highlighting their evolutionary significance. ConclusionThis is the first report unveiling a robust set of NUIs defining the pangenome of Bos indicus breeds of India. The analyses contribute valuable insights into the genomic landscape of desi cattle breeds.

genomics↗

polishCLR: a Nextflow workflow for polishing PacBio CLR genome assemblies

Long-read sequencing has revolutionized genome assembly, yielding highly contiguous, chromosome-level contigs. However, assemblies from some third generation long read technologies, such as Pacific Biosciences (PacBio) Continuous Long Reads (CLR), have a high error rate. Such errors can be corrected with short reads through a process called polishing. Although best practices for polishing non-model de novo genome assemblies were recently described by the Vertebrate Genome Project (VGP) Assembly community, there is a need for a publicly available, reproducible workflow that can be easily implemented and run on a conventional high performance computing environment. Here, we describe polishCLR (https://github.com/isugifNF/polishCLR), a reproducible Nextflow workflow that implements best practices for polishing assemblies made from CLR data. PolishCLR can be initiated from several input options that extend best practices to suboptimal cases. It also provides re-entry points throughout several key processes including identifying duplicate haplotypes in purge_dups, allowing a break for scaffolding if data are available, and throughout multiple rounds of polishing and evaluation with Arrow and FreeBayes. PolishCLR is containerized and publicly available for the greater assembly community as a tool to complete assemblies from existing, error-prone long-read data.

bioinformatics↗

Bovine pangenome reveals trait-associated structural variation from diverse assembly inputs

Advantages of pangenomes over linear reference assemblies for genome research have recently been established. However, potential effects of sequence platform and assembly approach, or of combining assemblies created by different approaches, on pangenome construction have not been investigated. We generated haplotype-resolved assemblies from the offspring of three bovine trios representing increasing levels of heterozygosity that each demonstrate a substantial improvement in contiguity, completeness, and accuracy over the current Bos taurus reference genome. Diploid coverage as low as 20x for HiFi or 60x for ONT was sufficient to produce two haplotype-resolved assemblies meeting the standards set by the Vertebrate Genome Project. Structural variant-based pangenomes created from the haplotype-resolved assemblies demonstrated significant consensus regardless of sequence platform, assembler algorithm, or coverage. Inspecting pangenome topologies identified 90 thousand structural variants including 931 overlapping with coding sequences; this approach revealed variants affecting QRICH2, PRDM9, HSPA1A, TAS2R46, and GC that have potential to affect phenotype.

genomics↗

Genomic rearrangements have consequences for introgression breeding as revealed by genome assemblies of wild and cultivated lentil species

Understanding the genomic relationship between wild and cultivated genomes would facilitate access to the untapped variability found in crop wild relatives. We developed genome assemblies of a cultivated lentil (Lens culinaris) as well as a wild relative (L. ervoides). Comparative analyses revealed large-scale structural rearrangements and additional repetitive DNA in the cultivated genome, resulting in regions of reduced recombination, segregation distortion and permanent heterozygosity in the offspring of a cross between the two species. These novel findings provide plant breeders with better insight into how best to approach accessing the novel variability available in wild relatives.

plant biology↗

A comprehensive catalogue of regulatory variants in the cattle transcriptome

Characterization of genetic regulatory variants acting on the transcriptome of livestock is essential for interpreting the molecular mechanisms underlying traits of economic value and for increasing the rate of genetic gain through artificial selection. Here, we build a cattle Genotype-Tissue Expression atlas (cattle GTEx, http://cgtex.roslin.ed.ac.uk/) as part of the pilot phase of Farm animal GTEx (FarmGTEx) project for the research community based on publicly available 11,642 RNA-Seq datasets. We describe the landscape of the transcriptome across over 100 tissues and report hundreds of thousands of genetic associations with gene expression and alternative splicing for 24 major tissues. We evaluate the tissue-sharing patterns of these genetic regulatory effects, and functionally annotate them using multi-omics data. Finally, we link gene expression in different tissues to 43 economically important traits using both transcriptome-wide association study (TWAS) and colocalization analyses to decipher the molecular regulatory mechanisms underpinning such agronomic traits in cattle.

genomics↗

Desert Dingo (Canis lupus dingo) genome provides insights into their role in the Australian ecosystem.

The dingo is Australias iconic top-order predator and arrived on the continent between 5,000-8,000 years ago. To provide an unbiased insight into its evolutionary affiliations and biological interactions, we coupled long-read DNA sequencing with a multiplatform scaffolding approach to produce an ab initio genome assembly of the desert dingo (85X coverage) we call CanLup_DDS. We compared this genome to the Boxer (CanFam3.1) and German Shepherd dog (CanFam_GSD) assemblies and characterized lineage-specific and shared genetic variation ranging from single- to megabase pair-sized variants. We identified 21,483 dingo-specific and 16,595 domestic dog-specific homozygous structural variants mediating genic and putative regulatory changes. Comparisons between the dingo and domestic dog builds detected unique inversions on Chromosome 16, structural variations in genes linked with starch metabolism, and seven differentially methylated genes. To experimentally assess genomic differences 17 dingoes and 15 German Shepherd dogs were fed parallel diets for 14 days. In dingoes, low AMY2B copy number and serum amylase levels are linked with high cholesterol and LDL levels. Gut microbiome analyses revealed enrichment of the family Clostridiaceae, which can utilize complex resistant starch, while scat metabolome studies identified high phenylethyl alcohol concentrations that we posit are linked with territory marking. Our study provides compelling genomic, microbiome, and metabolomic links showing the dingo has distinct physiology from domestic breed dogs with a unique role in the ecosystem.

genomics↗

Chromosome-length genome assembly and structural variations of the primal Basenji dog (Canis lupus familiaris) genome

BackgroundBasenjis are considered an ancient dog breed of central African origins that still live and hunt with tribesmen in the African Congo. Nicknamed the barkless dog, Basenjis possess unique phylogeny, geographical origins and traits, making their genome structure of great interest. The increasing number of available canid reference genomes allows us to examine the impact the choice of reference genome makes with regard to reference genome quality and breed relatedness. ResultsHere, we report two high quality de novo Basenji genome assemblies: a female, China (CanFam_Bas), and a male, Wags. We conduct pairwise comparisons and report structural variations between assembled genomes of three dog breeds: Basenji (CanFam_Bas), Boxer (CanFam3.1) and German Shepherd Dog (GSD) (CanFam_GSD). CanFam_Bas is superior to CanFam3.1 in terms of genome contiguity and comparable overall to the high quality CanFam_GSD assembly. By aligning short read data from 58 representative dog breeds to three reference genomes, we demonstrate how the choice of reference genome significantly impacts both read mapping and variant detection. ConclusionsThe growing number of high-quality canid reference genomes means the choice of reference genome is an increasingly critical decision in subsequent canid variant analyses. The basal position of the Basenji makes it suitable for variant analysis for targeted applications of specific dog breeds. However, we believe more comprehensive analyses across the entire family of canids is more suited to a pangenome approach. Collectively this work highlights the importance the choice of reference genome makes in all variation studies.

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↗

Chromosome-length haplotigs for yak and cattle from trio binning assembly of an F1 hybrid

BackgroundAssemblies of diploid genomes are generally unphased, pseudo-haploid representations that do not correctly reconstruct the two parental haplotypes present in the individual sequenced. Instead, the assembly alternates between parental haplotypes and may contain duplications in regions where the parental haplotypes are sufficiently different. Trio binning is an approach to genome assembly that uses short reads from both parents to classify long reads from the offspring according to maternal or paternal haplotype origin, and is thus helped rather than impeded by heterozygosity. Using this approach, it is possible to derive two assemblies from an individual, accurately representing both parental contributions in their entirety with higher continuity and accuracy than is possible with other methods.\n\nResultsWe used trio binning to assemble reference genomes for two species from a single individual using an interspecies cross of yak (Bos grunniens) and cattle (Bos taurus). The high heterozygosity inherent to interspecies hybrids allowed us to confidently assign >99% of long reads from the F1 offspring to parental bins using unique k-mers from parental short reads. Both the maternal (yak) and paternal (cattle) assemblies contain over one third of the acrocentric chromosomes, including the two largest chromosomes, in single haplotigs.\n\nConclusionsThese haplotigs are the first vertebrate chromosome arms to be assembled gap-free and fully phased, and the first time assemblies for two species have been created from a single individual. Both assemblies are the most continuous currently available for non-model vertebrates.

bioinformatics↗

Haplotype-Resolved Cattle Genomes Provide Insights Into Structural Variation and Adaptation

We present high quality, phased genome assemblies representative of taurine and indicine cattle, subspecies that differ markedly in productivity-related traits and environmental adaptation. We report a new haplotype-aware scaffolding and polishing pipeline using contigs generated by the trio binning method to produce haplotype-resolved, chromosome-level genome assemblies of Angus (taurine) and Brahman (indicine) cattle breeds. These assemblies were used to identify structural and copy number variants that differentiate the subspecies and we found variant detection was sensitive to the specific reference genome chosen. Six gene families with immune related functions are expanded in the indicine lineage. Assembly of the genomes of both subspecies from a single individual enabled transcripts to be phased to detect allele-specific expression, and to study genome-wide selective sweeps. An indicus-specific extra copy of fatty acid desaturase is under positive selection and may contribute to indicine adaptation to heat and drought.

genomics↗

An improved pig reference genome sequence to enable pig genetics and genomics research

The domestic pig (Sus scrofa) is important both as a food source and as a biomedical model with high anatomical and immunological similarity to humans. The draft reference genome (Sscrofa10.2) of a purebred Duroc female pig established using older clone-based sequencing methods was incomplete and unresolved redundancies, short range order and orientation errors and associated misassembled genes limited its utility. We present two annotated highly contiguous chromosome-level genome assemblies created with more recent long read technologies and a whole genome shotgun strategy, one for the same Duroc female (Sscrofa11.1) and one for an outbred, composite breed male (USMARCv1.0). Both assemblies are of substantially higher (>90-fold) continuity and accuracy than Sscrofa10.2. These highly contiguous assemblies plus annotation of a further 11 short read assemblies provide an unprecedented view of the genetic make-up of this important agricultural and biomedical model species. We propose that the improved Duroc assembly (Sscrofa11.1) become the reference genome for genomic research in pigs.

genomics↗