Genetics and Genomics Commons^™

Decoding The Equine Genome: Lessons From Encode, Sichong Peng, Jessica L. Petersen, Rebecca R. Bellone, Theodore S. Kalbfleisch, N. B. Kingsley, Alexa M. Barber, Eleonora Cappelletti, Elena Giulotto, Carrie J. Finno

Veterinary Science Faculty Publications

The horse reference genome assemblies, EquCab2.0 and EquCab3.0, have enabled great advancements in the equine genomics field, from tools to novel discoveries. However, significant gaps of knowledge regarding genome function remain, hindering the study of complex traits in horses. In an effort to address these gaps and with inspiration from the Encyclopedia of DNA Elements (ENCODE) project, the equine Functional Annotation of Animal Genome (FAANG) initiative was proposed to bridge the gap between genome and gene expression, providing further insights into functional regulation within the horse genome. Three years after launching the initiative, the equine FAANG group has generated data …

Successful Atac-Seq From Snap-Frozen Equine Tissues, Sichong Peng, Rebecca Bellone, Jessica L. Petersen, Theodore S. Kalbfleisch, Carrie J. Finno

Veterinary Science Faculty Publications

An assay for transposase-accessible chromatin with high-throughput sequencing (ATAC-seq) has become an increasingly popular method to assess genome-wide chromatin accessibility in isolated nuclei from fresh tissues. However, many biobanks contain only snap-frozen tissue samples. While ATAC-seq has been applied to frozen brain tissues in human, its applicability in a wide variety of tissues in horse remains unclear. The Functional Annotation of Animal Genome (FAANG) project is an international collaboration aimed to provide high quality functional annotation of animal genomes. The equine FAANG initiative has generated a biobank of over 80 tissues from two reference female animals and experiments to begin …

“Adopt-A-Tissue” Initiative Advances Efforts To Identify Tissue-Specific Histone Marks In The Mare, N. B. Kingsley, Natasha A. Hamilton, Gabriella Lindgren, Ludovic Orlando, Ernest Bailey, Samantha Brooks, Molly Mccue, Theodore S. Kalbfleisch, James N. Macleod, Jessica L. Petersen, Carrie J. Finno, Rebecca R. Bellone

Maxwell H. Gluck Equine Research Center Faculty Publications

No abstract provided.

Whole Genome Sequencing Identified A 16 Kilobase Deletion On Eca13 Associated With Distichiasis In Friesian Horses, E. A. Hisey, H. Hermans, Z. T. Lounsberry, F. Avila, R. A. Grahn, K. E. Knickelbein, S. A. Duward-Akhurst, M. E. Mccue, Theodore S. Kalbfleisch, M. E. Lassaline, W. Back, R. R. Bellone

Veterinary Science Faculty Publications

BACKGROUND: Distichiasis, an ocular disorder in which aberrant cilia (eyelashes) grow from the opening of the Meibomian glands of the eyelid, has been reported in Friesian horses. These misplaced cilia can cause discomfort, chronic keratitis, and corneal ulceration, potentially impacting vision due to corneal fibrosis, or, if secondary infection occurs, may lead to loss of the eye. Friesian horses represent the vast majority of reported cases of equine distichiasis, and as the breed is known to be affected with inherited monogenic disorders, this condition was hypothesized to be a simply inherited Mendelian trait.

RESULTS: A genome wide association study (GWAS) …

The P-Glycoprotein Repertoire Of The Equine Parasitic Nematode Parascaris Univalens, Alexander P. Gerhard, Jürgen Krücken, Emanuel Heitlinger, I. Jana I. Janssen, Marta Basiaga, Sławomir Kornaś, Céline Beier, Martin K. Nielsen, Richard E. Davis, Jianbin Wang, Georg Von Samson-Himmelstjerna

Maxwell H. Gluck Equine Research Center Faculty Publications

P-glycoproteins (Pgp) have been proposed as contributors to the widespread macrocyclic lactone (ML) resistance in several nematode species including a major pathogen of foals, Parascaris univalens. Using new and available RNA-seq data, ten different genomic loci encoding Pgps were identified and characterized by transcriptome-guided RT-PCRs and Sanger sequencing. Phylogenetic analysis revealed an ascarid-specific Pgp lineage, Pgp-18, as well as two paralogues of Pgp-11 and Pgp-16. Comparative gene expression analyses in P. univalens and Caenorhabditis elegans show that the intestine is the major site of expression but individual gene expression patterns were not conserved between the two nematodes. In P. …

Genome Diversity And The Origin Of The Arabian Horse, Elissa J. Cosgrove, Raheleh Sadeghi, Florencia Schlamp, Heather M. Holl, Mohammad Moradi-Shahrbabak, Seyed Reza Miraei-Ashtiani, Salma Abdalla, Ben Shykind, Mats H. T. Troedsson, Monika Stefaniuk-Szmukier, Anil Prabhu, Stefania Bucca, Monika Bugno-Poniewierska, Barbara Wallner, Joel Malek, Donald C. Miller, Andrew G. Clark, Douglas F. Antczak, Samantha A. Brooks

Veterinary Science Faculty Publications

The Arabian horse, one of the world's oldest breeds of any domesticated animal, is characterized by natural beauty, graceful movement, athletic endurance, and, as a result of its development in the arid Middle East, the ability to thrive in a hot, dry environment. Here we studied 378 Arabian horses from 12 countries using equine single nucleotide polymorphism (SNP) arrays and whole-genome re-sequencing to examine hypotheses about genomic diversity, population structure, and the relationship of the Arabian to other horse breeds. We identified a high degree of genetic variation and complex ancestry in Arabian horses from the Middle East region. Also, …

Equine Arteritis Virus Long-Term Persistence Is Orchestrated By Cd8+ T Lymphocyte Transcription Factors, Inhibitory Receptors, And The Cxcl16/Cxcr6 Axis, Mariano Carossino, Pouya Dini, Theodore S. Kalbfleisch, Alan T. Loynachan, Igor F. Canisso, R. Frank Cook, Peter J. Timoney, Udeni B. R. Balasuriya

Veterinary Science Faculty Publications

Equine arteritis virus (EAV) has the unique ability to establish long-term persistent infection in the reproductive tract of stallions and be sexually transmitted. Previous studies showed that long-term persistent infection is associated with a specific allele of the CXCL16 gene (CXCL16S) and that persistence is maintained despite the presence of local inflammatory and humoral and mucosal antibody responses. Here, we performed transcriptomic analysis of the ampullae, the primary site of EAV persistence in long-term EAV carrier stallions, to understand the molecular signatures of viral persistence. We demonstrated that the local CD8⁺ T lymphocyte response is predominantly orchestrated …

Kinetics Of The Chromosome 14 Microrna Cluster Ortholog And Its Potential Role During Placental Development In The Pregnant Mare, Pouya Dini, Peter Daels, Shavahn C. Loux, Alejandro Esteller-Vico, Mariano Carossino, Kirsten E. Scoggin, Barry A. Ball

Maxwell H. Gluck Equine Research Center Faculty Publications

Background: The human chromosome 14 microRNA cluster (C14MC) is a conserved microRNA (miRNA) cluster across eutherian mammals, reported to play an important role in placental development. However, the expression kinetics and function of this cluster in the mammalian placenta are poorly understood. Here, we evaluated the expression kinetics of the equine C24MC, ortholog to the human C14MC, in the chorioallantoic membrane during the course of gestation.

Results: We demonstrated that C24MC-associated miRNAs presented a higher expression level during early stages of pregnancy, followed by a decline later in gestation. Evaluation of one member of C24MC (miR-409-3p) by in situ hybridization …

Improved Reference Genome For The Domestic Horse Increases Assembly Contiguity And Composition, Theodore S. Kalbfleisch, Edward S. Rice, Michael S. Depriest Jr., Brian P. Walenz, Matthew S. Hestand, Joris R. Vermeesch, Brendan L. O'Connell, Ian T. Fiddes, Alisa O. Vershinina, Nedda F. Saremi, Jessica L. Petersen, Carrie J. Finno, Rebecca R. Bellone, Molly E Mccue, Samantha A. Brooks, Ernest Bailey, Ludovic Orlando, Richard E. Green, Donald C. Miller, Douglas F. Antczak, James N. Macleod

Maxwell H. Gluck Equine Research Center Faculty Publications

Recent advances in genomic sequencing technology and computational assembly methods have allowed scientists to improve reference genome assemblies in terms of contiguity and composition. EquCab2, a reference genome for the domestic horse, was released in 2007. Although of equal or better quality compared to other first-generation Sanger assemblies, it had many of the shortcomings common to them. In 2014, the equine genomics research community began a project to improve the reference sequence for the horse, building upon the solid foundation of EquCab2 and incorporating new short-read data, long-read data, and proximity ligation data. Here, we present EquCab3. The count of …

Horse Y Chromosome Assembly Displays Unique Evolutionary Features And Putative Stallion Fertility Genes, Jan E. Janečka, Brian W. Davis, Sharmila Ghosh, Nandina Paria, Pranab J. Das, Ludovic Orlando, Mikkel Schubert, Martin K. Nielsen, Tom A. E. Stout, Wesley Brashear, Gang Li, Charles D. Johnson, Richard P. Metz, Al Muatasim Al Zadjali, Charles C. Love, Dickson D. Varner, Daniel W. Bellott, William J. Murphy, Bhanu P. Chowdhary, Terje Raudsepp

Veterinary Science Faculty Publications

Dynamic evolutionary processes and complex structure make the Y chromosome among the most diverse and least understood regions in mammalian genomes. Here, we present an annotated assembly of the male specific region of the horse Y chromosome (eMSY), representing the first comprehensive Y assembly in odd-toed ungulates. The eMSY comprises single-copy, equine specific multi-copy, PAR transposed, and novel ampliconic sequence classes. The eMSY gene density approaches that of autosomes with the highest number of retained X–Y gametologs recorded in eutherians, in addition to novel Y-born and transposed genes. Horse, donkey and mule testis RNAseq reveals several candidate genes for stallion …

Genetic Signatures For Helicobacter Pylori Strains Of West African Origin, Kennady K. Bullock, Carrie L. Shaffer, Andrew W. Brooks, Ousman Secka, Mark H. Forsyth, Mark S. Mcclain, Timothy L. Cover

Veterinary Science Faculty Publications

Helicobacter pylori is a genetically diverse bacterial species that colonizes the stomach in about half of the human population. Most persons colonized by H. pylori remain asymptomatic, but the presence of this organism is a risk factor for gastric cancer. Multiple populations and subpopulations of H. pylori with distinct geographic distributions are recognized. Genetic differences among these populations might be a factor underlying geographic variation in gastric cancer incidence. Relatively little is known about the genomic features of African H. pylori strains compared to other populations of strains. In this study, we first analyzed the genomes of …

Developing A 670k Genotyping Array To Tag ~2m Snps Across 24 Horse Breeds, Robert J. Schaefer, Mikkel Schubert, Ernest F. Bailey, Danika L. Bannasch, Eric Barrey, Gila Kahila Bar-Gal, Gottfried Brem, Samantha A. Brooks, Ottmar Distl, Ruedi Fries, Carrie J. Finno, Vinzenz Gerber, Bianca Haase, Vidhya Jagannathan, Ted Kalbfleisch, Tosso Leeb, Gabriella Lindgren, Maria Susana Lopes, Núria Mach, Artur Da Câmara Machado, James N. Macleod, Annette Mccoy, Julia Metzger, Cecilia Penedo, Sagi Polani, Stefan Rieder, Imke Tammen, Jens Tetens, Georg Thaller, Andrea Verini-Supplizi

Gluck Equine Research Center Faculty Publications

Background: To date, genome-scale analyses in the domestic horse have been limited by suboptimal single nucleotide polymorphism (SNP) density and uneven genomic coverage of the current SNP genotyping arrays. The recent availability of whole genome sequences has created the opportunity to develop a next generation, high-density equine SNP array.

Results: Using whole genome sequence from 153 individuals representing 24 distinct breeds collated by the equine genomics community, we cataloged over 23 million de novo discovered genetic variants. Leveraging genotype data from individuals with both whole genome sequence, and genotypes from lower-density, legacy SNP arrays, a subset of ~5 million high-quality, …

Allelic Variation In Cxcl16 Determines Cd3+ T Lymphocyte Susceptibility To Equine Arteritis Virus Infection And Establishment Of Long-Term Carrier State In The Stallion, Sanjay Sarkar, Ernest Bailey, Yun Young Go, R. Frank Cook, Ted Kalbfleisch, John E. Eberth, R. Lakshman Chelvarajan, Kathleen M. Shuck, Sergey Artiushin, Peter J. Timoney, Udeni B. R. Balasuriya

Maxwell H. Gluck Equine Research Center Faculty Publications

Equine arteritis virus (EAV) is the causative agent of equine viral arteritis (EVA), a respiratory, systemic, and reproductive disease of horses and other equid species. Following natural infection, 10–70% of the infected stallions can become persistently infected and continue to shed EAV in their semen for periods ranging from several months to life. Recently, we reported that some stallions possess a subpopulation(s) of CD3⁺ T lymphocytes that are susceptible to in vitro EAV infection and that this phenotypic trait is associated with long-term carrier status following exposure to the virus. In contrast, stallions not possessing the CD3⁺ T …

Large Deletions At The Shox Locus In The Pseudoautosomal Region Are Associated With Skeletal Atavism In Shetland Ponies, Nima Rafati, Lisa S. Andersson, Sofia Mikko, Chungang Feng, Terje Raudsepp, Jessica Pettersson, Jan Janecka, Ove Wattle, Adam Ameur, Gunilla Thyreen, John E. Eberth, John Huddleston, Maika Malig, Ernest Bailey, Evan E. Eichler, Göran Dalin, Bhanu Chowdary, Leif Andersson, Gabriella Lindgren, Carl-Johan Rubin

Maxwell H. Gluck Equine Research Center Faculty Publications

Skeletal atavism in Shetland ponies is a heritable disorder characterized by abnormal growth of the ulna and fibula that extend the carpal and tarsal joints, respectively. This causes abnormal skeletal structure and impaired movements, and affected foals are usually killed. In order to identify the causal mutation we subjected six confirmed Swedish cases and a DNA pool consisting of 21 control individuals to whole genome resequencing. We screened for polymorphisms where the cases and the control pool were fixed for opposite alleles and observed this signature for only 25 SNPs, most of which were scattered on genome assembly unassigned scaffolds. …

Local Admixture Of Amplified And Diversified Secreted Pathogenesis Determinants Shapes Mosaic Toxoplasma Gondii Genomes, Hernan Lorenzi, Asis Khan, Michael S. Behnke, Sivaranjani Namasivayam, Lakshmipuram S. Swapna, Michalis Hadjithomas, Svetlana Karamycheva, Deborah Pinney, Brian P. Brunk, James W. Ajioka, Daniel Ajzenberg, John C. Boothroyd, Jon P. Boyle, Marie L. Dardé, Maria A. Diaz-Miranda, Jitender P. Dubey, Heather M. Fritz, Solange M. Gennari, Brian D. Gregory, Kami Kim, Jeroen P. J. Saeij, Chunlei Su, Michael W. White, Xing-Quan Zhu, Daniel K. Howe, Benjamin M. Rosenthal, Michael E. Grigg, John Parkinson, Liang Liu, Jessica C. Kissinger

Veterinary Science Faculty Publications

Toxoplasma gondii is among the most prevalent parasites worldwide, infecting many wild and domestic animals and causing zoonotic infections in humans. T. gondii differs substantially in its broad distribution from closely related parasites that typically have narrow, specialized host ranges. To elucidate the genetic basis for these differences, we compared the genomes of 62 globally distributed T. gondii isolates to several closely related coccidian parasites. Our findings reveal that tandem amplification and diversification of secretory pathogenesis determinants is the primary feature that distinguishes the closely related genomes of these biologically diverse parasites. We further show that the unusual population structure …