Genetics in horses encompasses the study of hereditary traits and the genetic makeup that influences various characteristics and health conditions in equine populations. This field involves the analysis of genes and their functions, inheritance patterns, and the impact of genetic variations on traits such as coat color, performance ability, and susceptibility to diseases. Research in equine genetics employs techniques such as genome mapping, sequencing, and genetic testing to identify specific genes and mutations associated with these traits. This page gathers peer-reviewed research studies and scholarly articles that explore the genetic basis of equine traits, the methodologies used in genetic research, and the implications for breeding, health management, and conservation of horse breeds.
Maniego J, Harding C, Habershon-Butcher J, Hincks P, Stewart G, Proudman C, Ryder E.Due to the ease of collection, transport and storage, the use of dried blood spots (DBS) offers an attractive alternative matrix for detection of the abuse of gene therapy, otherwise known as gene doping. This study evaluated the recovery, extraction efficiency and resulting detection capability of DNA from DBS by evaluating different target types, DNA extraction kits, the number of punches and blood tube preservatives. The long-term storage stability of low-copy-number transgene targets in DBS was not assessed in this study but would be noteworthy to investigate further. DNA was quantified us...
Ramírez-Agámez L, Castaneda C, Hernández-Avilés C, Grahn RA, Raudsepp T, Love CC.Two methods for preimplantation genetic testing (PGT) have been described for equine embryos: trophoblast cell biopsy (TCB) or blastocoele fluid aspiration (BFA). While TCB is widely applied for both in vivo- and in vitro-produced embryos, BFA has been mostly utilized for in vivo-produced embryos. Alternative methods for PGT, including analysis of cell-free DNA (CFD) in the medium where in vitro-produced embryos are cultured, have been reported in humans but not for equine embryos. In Experiment 1, in vivo- (n = 10) and in vitro-produced (n = 13) equine embryos were subjected to BFA, cultu...
Ewelina SG, Anna Z, Rafał P, Maciej W.Sarcoids are the most frequently diagnosed dermatological tumour in horses. It is a disease that can affect various species of equids, such as donkeys, mules and zebras. This type of tumour can develop in all horse breeds, regardless of age and gender. Treatment options depend on many factors, such as the type of lesion, location, extent, owner preference and financial considerations. In the present study, we investigated the TRIM29 expression, the methylation status of its first exon and its involvement in the formation of equine sarcoids. Bisulfite sequencing PCR (BSP) was used to determine ...
Kapusniak A, Nath L, Hebart M, Franklin S.Sudden cardiac death (SCD) is an important cause of exercise-associated fatalities in Thoroughbred racehorses. Equine deaths share similarities with fatalities in human athletes that result from inherited cardiac disease. Whilst genetic causes have been postulated in horses, these have not been confirmed and heritability of SCD has not previously been estimated in Thoroughbred racehorses. Objective: To determine the heritability of SCD in a sample population of Thoroughbred racehorses. Methods: Retrospective case-control study. Methods: Steward and post-mortem reports of Thoroughbred racehorse...
Pokharel K, Weldenegodguad M, Reilas T, Kantanen J.Finnhorse is Finland's native and national horse breed and it has genetic affinities to northern European and Asian horses. It has historical importance for agriculture, forest work and transport and as a war horse. Finnhorse has four breeding sections in the studbook and is under conservation and characterisation efforts. We sequenced and annotated the genome of a Finnhorse mare from the working horse section using PacBio and Omni-C data. This genome can complement the existing Thoroughbred reference genome (EquCab 3.0) and facilitate genetic studies of horses from northern Eurasia. We assemb...
Gmel AI, Mikko S, Ricard A, Velie BD, Gerber V, Hamilton NA, Neuditschko M.The Franches-Montagnes (FM) is the last native horse breed of Switzerland, established at the end of the 19th century by cross-breeding local mares with Anglo-Norman stallions. We collected high-density SNP genotype data (Axiom™ 670 K Equine genotyping array) from 522 FM horses, including 44 old-type horses (OF), 514 European Warmblood horses (WB) from Sweden and Switzerland (including a stallion used for cross-breeding in 1990), 136 purebred Arabians (AR), 32 Shagya Arabians (SA), and 64 Thoroughbred (TB) horses, as introgressed WB stallions showed TB origin in their pedigrees. The aim of ...
Onouchi S, Yoshida T, Saito S, Atoji Y.We examined the relationship between inherited motor-related conformation and orientation of facial hair whorls in Japanese Kiso horses. Eleven horses were divided into clockwise, counterclockwise, and radial groups according to facial hair whorls. We placed six markers on anatomical landmarks of each lateral side in a horse and measured the height of the landmarks, the distance between adjacent landmarks, and the angle of the adjacent landmarks. In the counterclockwise group, the horses tended to exhibit higher values on the left side than on the right side, and the comparison of the height o...
Tiwari M, Gujar G, Shashank CG, Ponsuksili S.High altitude adapted livestock species (cattle, yak, goat, sheep, and horse) has critical role in the human socioeconomic sphere and acts as good source of animal source products including milk, meat, and leather, among other things. These species sustain production and reproduction even in harsh environments on account of adaptation resulting from continued evolution of beneficial traits. Selection pressure leads to various adaptive strategies in livestock whose footprints are evident at the different genomic sites as the "Selection Signature". Scrutiny of these signatures provides us crucia...
Ustyantsev IG, Kosushkin SA, Borodulina OR, Vassetzky NS, Kramerov DA.Short Interspersed Elements (SINEs) are eukaryotic retrotransposons transcribed by RNA polymerase III (pol III). Many mammalian SINEs (T SINEs) contain a polyadenylation signal (AATAAA), a pol III transcription terminator, and an A-rich tail in their 3'-end. The RNAs of such SINEs have the capacity for AAUAAA-dependent polyadenylation, which is unique to pol III-generated transcripts. The structure, evolution, and polyadenylation of the Ere SINE of ungulates (horses, rhinos, and tapirs) were investigated in this study. A bioinformatics analysis revealed the presence of up to ~4 × 10 Ere copie...
Fegraeus K, Rosengren MK, Naboulsi R, Orlando L, Åbrink M, Jouni A, Velie BD, Raine A, Egner B, Mattsson CM, Lång K, Zhigulev A, Björck HM....The control of transcription is crucial for homeostasis in mammals. A previous selective sweep analysis of horse racing performance revealed a 19.6 kb candidate regulatory region 50 kb downstream of the Endothelin3 (EDN3) gene. Here, the region was narrowed to a 5.5 kb span of 14 SNVs, with elite and sub-elite haplotypes analyzed for association to racing performance, blood pressure and plasma levels of EDN3 in Coldblooded trotters and Standardbreds. Comparative analysis of human HiCap data identified the span as an enhancer cluster active in endothelial cells, interacting with genes relevant ...
Liu X, Peng Y, Zhang X, Wang X, Chen W, Kou X, Liang H, Ren W, Khan MZ, Wang C.Variation in coat color among equids has attracted significant interest in genetics and breeding research. The range of colors is primarily determined by the type, concentration, and distribution of melanin pigments, with the balance between eumelanin and pheomelanin influenced by numerous genetic factors. Advances in genomic and sequencing technologies have enabled the identification of several candidate genes that influence coat color, thereby clarifying the genetic basis of these diverse phenotypes. In this review, we concisely categorize coat coloration in horses and donkeys, focusing on t...
Derbala MK, Sargious MAN, Hagag NM, Pycock JF, Abu-Seida AM.Twin pregnancy in mares is one of the leading causes of abortions. Abortion invariably impacts both fetuses. This report describes an unusual case of a twin surviving to term following the abortion of its co-twin at 9 months in a 7-year-old Egyptian Arabian mare. At the time of abortion at 9 months of gestation, the size of the aborted fetus was equivalent to one of approximately 5 months of age while the age of the live co-twin was 9 months. Both fetuses were males. A skin sample was collected from the aborted fetus and hair samples were collected from the dam, sire and live foal for parentag...
Zhu S, Zhang N, Zhang J, Shao X, Guo Y, Cai D.This study analyzed ancient DNA from the remains of horses unearthed from the Shihuyao tombs. These were found to date from the Han and Tang Dynasties in Xinjiang (approximately 2200 to 1100 years ago). Two high-quality mitochondrial genomes were acquired and analyzed using next-generation sequencing. The genomes were split into two maternal haplogroups, B and D, according to a study that included ancient and contemporary samples from Eurasia. A close genetic affinity was observed between the horse of the Tang Dynasty and Akhal-Teke horses according to the primitive horse haplotype G1. Histori...
Reich P, Möller S, Stock KF, Nolte W, von Depka Prondzinski M, Reents R, Kalm E, Kühn C, Thaller G, Falker-Gieske C, Tetens J.Body conformation, including withers height, is a major selection criterion in horse breeding and is associated with other important traits, such as health and performance. However, little is known about the genomic background of equine conformation. Therefore, the aim of this study was to use imputed sequence-level genotypes from up to 4891 German Warmblood horses to identify genomic regions associated with withers height and linear conformation traits. Furthermore, the traits were genetically characterised and putative causal variants for withers height were detected. Results: A genome-wide ...
Yokomori T, Tozaki T, Ohnuma A, Ishimaru M, Sato F, Hori Y, Segawa T, Itou T.Retraining retired racehorses for various purposes can help correct behavioral issues. However, ensuring efficiency and preventing accidents present global challenges. Based on the hypothesis that a simple personality assessment could help address these challenges, the present study aimed to identify genetic markers associated with personality. Eight genes were selected from 18 personality-related candidate genes that are orthologs of human personality genes, and their association with personality was verified based on actual behavior. A total of 169 Thoroughbred horses were assessed for their...
Furukawa R, Tozaki T, Kikuchi M, Ishige T, Takahashi Y, Fukui E, Kakoi H.Gene doping is prohibited in horse sports and can involve the administration of exogenous genes, called transgenes, to postnatal animals. Quantitative polymerase chain reaction (qPCR) methods have been developed to detect gene doping; however, these generally require DNA extraction from the plasma prior to qPCR. In this study, we developed two methods, direct droplet digital PCR (ddPCR) and nested ddPCR, to detect the equine erythropoietin (EPO) transgene without DNA extraction. Direct ddPCR used pretreated plasma and PCR to detect the EPO transgene spiked at 10 copies/μL. Nested ddPCR utilis...
Amiri Roudbar M, Rosengren MK, Mousavi SF, Fegraeus K, Naboulsi R, Meadows JRS, Lindgren G.Elite performing exercise requires an intricate modulation of the blood pressure to support the working muscles with oxygen. We have previously identified a genomic regulatory module that associates with differences in blood pressures of importance for elite performance in racehorses. This study aimed to determine the effect of the regulatory module on the protein repertoire. We sampled plasma from 12 Coldblooded trotters divided into two endothelial regulatory module haplotype groups, a sub-elite performing haplotype (SPH) and an elite performing haplotype (EPH), each at rest and exercise. Th...
Hernández-Avilés C, Ramírez-Agámez L, Weintraub ST, Scoggin CF, Davis BW, Raudsepp T, Varner DD, Love CC.Thoroughbred stallions that carry a double-homozygous genotype A/A-A/A for SNPs rs397316122 and rs69101140 in exon 5 of the FKBP6 gene (chr13; EquCab3.0) are uniquely subfertile due to impaired acrosomal exocytosis (IAE). In this study, the sperm proteome in frozen/thawed semen from subfertile Thoroughbred stallions was studied and compared to that of frozen/thawed sperm from fertile Thoroughbred stallions. A total of 2,220 proteins was identified, of which 140 proteins were found to be differentially abundant in sperm from the subfertile stallions compared to that of fertile stallions (83 les...
Flack N, Hughes L, Cassens J, Enriquez M, Gebeyehu S, Alshagawi M, Hatfield J, Kauffman A, Brown B, Klaeui C, Mabrouk IF, Walls C, Yeater T, Rivas A....The Przewalski's horse (Equus ferus przewalskii) is an endangered equid native to the steppes of central Asia. After becoming extinct in the wild multiple conservation efforts convened to preserve the species, including captive breeding programs, reintroduction and monitoring systems, protected lands, and cloning. Availability of a highly contiguous reference genome is essential to support these continued efforts. We used Oxford Nanopore sequencing to produce a scaffold-level 2.5 Gb nuclear assembly and 16,002 bp mitogenome from a captive Przewalski's mare. All assembly drafts were generated f...
Bugno-Poniewierska M, Jankowska M, Raudsepp T, Kowalska K, Pawlina-Tyszko K, Szmatola T.Chromosomal abnormalities occur in the equine population at a rate of approximately 2%. The use of molecular cytogenetic techniques allows a more accurate identification of chromosomal abnormalities, especially those with a low rate of abnormal metaphases, demonstrating that the actual incidence in equine populations is higher. Objective: Estimation of the number of carriers of karyotypic abnormalities in a sample from a population of young horses of various breeds, using molecular cytogenetic techniques. Methods: Cross-sectional. Methods: Venous blood samples were collected from 500 young hor...
Muko R, Ojima Y, Matsuda H, Toishi Y, Oikawa MA, Shin T, Sato H, Tanaka A.Previously, we demonstrated unique insertion/deletion polymorphisms of equine histidine-rich glycoprotein with five genotypes composed of 45-bp or 90-bp deletions in the histidine-rich region of in Thoroughbred horses. Although leukocytes are typically used to collect DNA for genotyping, blood sampling from animals is sometimes difficult and invasive. Moreover, the method for extracting DNA from blood leukocytes involves complicated steps and must be performed soon after blood sampling for sensitive gene analysis. In the present study, we performed genotyping using DNA, isolated from oral m...
French KM, Musiał AD, Karczewski M, Daugnora L, Shiroukhov R, Ropka-Molik K, Baranowski T, Bertašius M, Skvortsov K, Szymański P....Horse sacrifice and deposition are enigmatic features of funerary rituals identified across prehistoric Europe that persisted in the eastern Baltic. Genetic and isotopic analysis of horses in Balt cemeteries [1st to 13th centuries CE (Common Era)] dismantle prevailing narratives that locally procured stallions were exclusively selected. Strontium isotope analysis provides direct evidence for long-distance (~300 to 1500 kilometers) maritime transport of Fennoscandian horses to the eastern Baltic in the Late Viking Age (11th to 13th centuries CE). Genetic analysis proves that horses of both sexe...
Azcona F, Karlau A, Trigo P, Molina A, Demyda-Peyrás S.The Polo Argentino (PA) horse is a recognized breed, developed originally by mixing crossbred and Thoroughbred (TB) horses to play polo. Early PA selection is difficult due to unreliable performance estimations. This study investigated the usefulness of genomic markers previously linked to morphological and functional traits as a tool for the early selection of PA. To this, we genotyped 520 PA and 30 TB horses using the Equine GGPArray (Illumina, n=71,778 SNPs). Analyses included a genetic characterization of six genetic markers associated with behavioral (DRD4), muscular development (MSTN), a...
Steensma MJ, Doekes HP, Pook T, Derks MFL, Bakker N, Ducro BJ.In the past, small population sizes and unequal ancestor contributions have resulted in high inbreeding rates (ΔF) in the Friesian horse. Two decades ago, the studbook implemented a mating quota and started publishing individual kinships and reduced ΔF below 1% per generation. However, since then, the breeding population size has decreased and this raises the question whether current breeding strategies are sufficient to keep ΔF below desired rates. The aim of this study was to (1) reflect on past inbreeding trends and their main determinants, using pedigree analysis and (2) evaluate the ef...
Young AE, Finno CJ.Equine neuroaxonal dystrophy/equine degenerative myeloencephalopathy (eNAD/EDM) is an inherited neurodegenerative disease associated with vitamin E deficiency in the first year of life. It is the second most common cause of spinal ataxia in horses euthanized for neurologic disease. Equine NAD/EDM is characterized by neurologic signs including a symmetric proprioceptive ataxia (> grade 2/5) and a wide-base stance at rest. There are currently no antemortem tests for eNAD/EDM in any breed. Conclusive diagnosis requires postmortem histologic evaluation of the brainstem and spinal cord at necropsy....
Yi M, Asgenbaatar N, Wang X, Ulaangerel T, Shen Y, Wen X, Du M, Dong X, Dugarjav M, Bou G.DNA methyltransferases (DNMTs) are important epigenetic modification during spermatogenesis. To further evaluate the pattern of DNMTs in horse testes during development, we investigated the expression and localization of DNMT1, DNMT3a and DNMT3b at different time points. The qRT-PCR results showed that DNMT1 expression was maintained in testes tissue from 6-month-old (0.5y) to 2-year-old (2y) of age and decreased after 3-year-old (3y) (P < 0.01). The expression levels of DNMT3a and DNMT3b peaked in testes tissue at 3y (P < 0.01). At 4-year-old (4y), the expression of DNMT3a and DNMT3b was ...
Liu Y, Du M, Li X, Zhang L, Zhao B, Wang N, Dugarjaviin M.This study aimed to investigate differences in testicular tissue morphology, gene expression, and marker genes between sexually immature (1-year-old) and sexually mature (10-year-old) Mongolian horses. The purposes of our research were to provide insights into the reproductive physiology of male Mongolian horses and to identify potential markers for sexual maturity. The methods we applied included the transcriptomic profiling of testicular cells using single-cell sequencing techniques. Our results revealed significant differences in tissue morphology and gene expression patterns between the tw...
Aminou O, Badaoui B, Machmoum M, Piro M.The International Society for Animal Genetics (ISAG) currently advocates for a transition towards single nucleotide polymorphism (SNP) markers as a potential alternative for equine parentage verification. To ascertain the efficacy of this transition, it is imperative to evaluate the performance of parentage testing using SNPs in juxtaposition with short tandem repeats (STRs). As per ISAG's recommendation, we used an equine genotyping-by-sequencing panel with 144 SNPs for this purpose. Equine parentage is currently realized using 16 microsatellites (STRs) excluding the LEX3 marker. In this stud...
Cortez JV, Hardwicke K, Grupen CG, Herrid M, Machaty Z, Vajta G.A 6-year-old mare, a valuable polo horse, died of complications following postcolic surgery. To preserve its genetics, ear skin samples were collected immediately after death and stored in an equine embryo transfer medium at 4°C for 5 days. After trypsin digestion, monolayer fibroblast cultures were established, but signs of massive bacterial infection were found in all of them. As an ultimate attempt for rescue, rigorously and repeatedly washed cells were individually cultured in all wells of four 96-well dishes. New monolayers were established from the few wells without contamination and us...
Weckman MJ, Karikoski NP, Raekallio MR, Box JR, Kvist L.Equine metabolic syndrome (EMS) is a common welfare problem in horses worldwide. It is characterized by insulin dysregulation (ID), predisposition to laminitis and often obesity. EMS is multifactorial by nature, with both the environment and genetics contributing to the phenotype. Environmental factors, such as feeding and exercise, can be controlled, thus forming the basis for treatment and prevention. Genetic factors, by contrast, are less well-known and not easily controllable. The aim of this study was to identify potential genetic loci influencing ID/EMS in Finnhorses. A single-breed (Fin...
Morens DM, Taubenberger JK.To understand human influenza in a historical context of viral circulation in avian species, mammals, and in the environment. Methods: Historical review. Methods: Global events in a variety of circumstances over more than 3,000 years time. Methods: Comprehensive review of the historical literature including all major publications on pandemic and panzootic influenza. Methods: Influenza pandemics, panzootics, major epidemics and epizootics, and instances of interspecies transmission of influenza A. Results: Extensive documentation of human and animal influenza over many centuries suggests that i...
de Laat MA, McGree JM, Sillence MN.Compared with some other species, insulin dysregulation in equids is poorly understood. However, hyperinsulinemia causes laminitis, a significant and often lethal disease affecting the pedal bone/hoof wall attachment site. Until recently, hyperinsulinemia has been considered a counterregulatory response to insulin resistance (IR), but there is growing evidence to support a gastrointestinal etiology. Incretin hormones released from the proximal intestine, glucagon-like peptide-1 (GLP-1) and glucose-dependent insulinotropic peptide, augment insulin secretion in several species but require invest...
Browning GF, Fitzgerald TA, Chalmers RM, Snodgrass DR.Equine rotavirus FI23 was shown to be prototypic of a novel G serotype, provisionally G14, by cross-neutralization and VP7 sequence determination. Although distinct, there are as few as six differing amino acid residues (92, 94, 96, 146, 147, and 221) in the VP7 antigenic regions of FI23 and G3 rotaviruses.
Leroux C, Issel CJ, Montelaro RC.We have investigated the genetic evolution of three functionally distinct regions of the equine infectious anemia virus (EIAV) genome (env, rev, and long terminal repeat) during recurring febrile episodes in a pony experimentally infected with a well-characterized reference biological clone designated EIAV(PV). Viral populations present in the plasma of an EIAV(PV)-infected pony during sequential febrile episodes (18, 34, 80, 106, and 337 days postinfection) were amplified from viral RNA, analyzed, and compared to the inoculated strain. The comparison of the viral quasispecies showed that the ...
Mammalian centromeres are associated with highly repetitive DNA (satellite DNA), which has so far hindered molecular analysis of this chromatin domain. Centromeres are epigenetically specified, and binding of the CENPA protein is their main determinant. In previous work, we described the first example of a natural satellite-free centromere on Chromosome 11. Here, we investigated the satellite-free centromeres of by using ChIP-seq with anti-CENPA antibodies. We identified an extraordinarily high number of centromeres lacking satellite DNA (16 of 31). All of them lay in LINE- and AT-rich regio...
Brüssow H, Brüssow L.Contemporary medical reports from Britain and Germany on patients suffering from a pandemic infection between 1889 and 1891, which was historically referred to as the Russian flu, share a number of characteristics with COVID-19. Most notable are aspects of multisystem affections comprising respiratory, gastrointestinal and neurological symptoms including loss of taste and smell perception; a protracted recovery resembling long covid and pathology observations of thrombosis in multiple organs, inflammation and rheumatic affections. As in COVID-19 and unlike in influenza, mortality was seen in e...
Shehu-Xhilaga M, Ablan S, Demirov DG, Chen C, Montelaro RC, Freed EO.The Gag proteins of a number of different retroviruses contain late or L domains that promote the release of virions from the plasma membrane. Three types of L domains have been identified to date: Pro-Thr-Ala-Pro (PTAP), Pro-Pro-X-Tyr, and Tyr-Pro-Asp-Leu. It has previously been demonstrated that overexpression of the N-terminal, E2-like domain of the endosomal sorting factor TSG101 (TSG-5') inhibits human immunodeficiency virus type 1 (HIV-1) release but does not affect the release of the PPPY-containing retrovirus murine leukemia virus (MLV), whereas overexpression of the C-terminal portion...
Nemoto M, Bannai H, Tsujimura K, Kobayashi M, Kikuchi T, Yamanaka T, Kondo T.An outbreak of Getah virus infection occurred among racehorses in Japan during September and October 2014. Of 49 febrile horses tested by reverse transcription PCR, 25 were positive for Getah virus. Viruses detected in 2014 were phylogenetically different from the virus isolated in Japan in 1978.
Miller TL, Lin C.Formal nomenclature is proposed for five methanogens, isolated from horse, pig, cow, goose and sheep faeces, that represent four novel species of the genus Methanobrevibacter. The four species, Methanobrevibacter gottschalkii sp. nov., Methanobrevibacter thaueri sp. nov., Methanobrevibacter woesei sp. nov. and Methanobrevibacter wolinii sp. nov., are distinguished from each other by a lack of genomic DNA reassociation and from previously described members of the genus on the basis of differences in the sequences of the 16S rRNA genes.
Evans SV, Brayer GD.The three-dimensional structure of horse heart metmyoglobin has been refined to a final R-factor of 15.5% for all observed data in the 6.0 to 1.9 A resolution range. The final model consists of 1242 non-hydrogen protein atoms, 154 water molecules and one sulfate ion. This structure has nearly ideal bonding and bond angle geometry. A Luzzati plot of the variation in R-factor with resolution yields an estimated mean co-ordinate error of 0.18 A. An extensive analysis of the pattern of hydrogen bonds formed in horse heart metmyoglobin has been completed. Over 80% of the polypeptide chain is involv...
Janvilisri T, Scaria J, Thompson AD, Nicholson A, Limbago BM, Arroyo LG, Songer JG, Gröhn YT, Chang YF.Clostridium difficile is a gram-positive, spore-forming enteric anaerobe which can infect humans and a wide variety of animal species. Recently, the incidence and severity of human C. difficile infection has markedly increased. In this study, we evaluated the genomic content of 73 C. difficile strains isolated from humans, horses, cattle, and pigs by comparative genomic hybridization with microarrays containing coding sequences from C. difficile strains 630 and QCD-32g58. The sequenced genome of C. difficile strain 630 was used as a reference to define a candidate core genome of C. difficile a...
Payne SL, Fang FD, Liu CP, Dhruva BR, Rwambo P, Issel CJ, Montelaro RC.The extent and nature of genomic variation among nine antigenically distinct EIAV isolates recovered during sequential clinical episodes from two experimentally infected ponies were examined by restriction fragment analysis and nucleotide sequencing. Only minor variations in restriction enzyme patterns were observed among the viral genomes. In contrast, env gene sequences of four isolates from one pony revealed numerous clustered base substitutions. Divergence in env gene nucleotide and deduced amino acid sequences between pairs of virus isolates ranged from 0.62 to 3.4% env gene mutation rate...
Webb K, Jolley KA, Mitchell Z, Robinson C, Newton JR, Maiden MCJ, Waller A.The zoonotic pathogen Streptococcus equi subsp. zooepidemicus (S. zooepidemicus) is commonly found harmlessly colonizing the equine nasopharynx. Occasionally, strains can invade host tissues or cross species barriers, and S. zooepidemicus is associated with numerous different diseases in a variety of hosts, including inflammatory airway disease and abortion in horses, pneumonia in dogs and meningitis in humans. A biovar of S. zooepidemicus, Streptococcus equi subsp. equi, is the causative agent of strangles, one of the most important infections of horses worldwide. We report here the developme...
Ramseyer A, Gaillard C, Burger D, Straub R, Jost U, Boog C, Marti E, Gerber V.Environment and genetics influence the manifestation of recurrent airway obstruction (RAO), but the associations of specific factors with mild, moderate, and severe clinical signs are unknown. Objective: We hypothesized that sire, feed, bedding, time outdoors, sex, and age are associated with clinical manifestations of mild, moderate, and severe lower airway disease. Methods: Direct offspring of 2 RAO-affected Warmblood stallions (F1S1, n = 172; F1S2, n = 135); maternal half-siblings of F1S1 (mHSS1, n = 66); and an age-matched, randomly chosen control group (CG, n = 33). Methods: A standardize...
Ghosh S, Qu Z, Das PJ, Fang E, Juras R, Cothran EG, McDonell S, Kenney DG, Lear TL, Adelson DL, Chowdhary BP, Raudsepp T.We constructed a 400K WG tiling oligoarray for the horse and applied it for the discovery of copy number variations (CNVs) in 38 normal horses of 16 diverse breeds, and the Przewalski horse. Probes on the array represented 18,763 autosomal and X-linked genes, and intergenic, sub-telomeric and chrY sequences. We identified 258 CNV regions (CNVRs) across all autosomes, chrX and chrUn, but not in chrY. CNVs comprised 1.3% of the horse genome with chr12 being most enriched. American Miniature horses had the highest and American Quarter Horses the lowest number of CNVs in relation to Thoroughbred r...
Antwis RE, Lea JMD, Unwin B, Shultz S.Microbiome composition is linked to host functional traits including metabolism and immune function. Drivers of microbiome composition are increasingly well-characterised; however, evidence of group-level microbiome convergence is limited and may represent a multi-level trait (i.e. across individuals and groups), whereby heritable phenotypes are influenced by social interactions. Here, we investigate the influence of spatial structuring and social interactions on the gut microbiome composition of Welsh mountain ponies. We show that semi-feral ponies exhibit variation in microbiome composition ...
Peffers M, Liu X, Clegg P.Age is an important factor in the development of osteoarthritis. Microarray studies provide insight into cartilage aging but do not reveal the full transcriptomic phenotype of chondrocytes such as small noncoding RNAs, pseudogenes, and microRNAs. RNA-Seq is a powerful technique for the interrogation of large numbers of transcripts including nonprotein coding RNAs. The aim of the study was to characterise molecular mechanisms associated with age-related changes in gene signatures. Methods: RNA for gene expression analysis using RNA-Seq and real-time PCR analysis was isolated from macroscopicall...
The Journal of hereditySeptember 1, 1991
Volume 82, Issue 5 369-377 doi: 10.1093/oxfordjournals.jhered.a111106
Wichman HA, Payne CT, Ryder OA, Hamilton MJ, Maltbie M, Baker RJ.We describe a molecular model for rapid chromosomal evolution that proposes tandemly repeated DNA sequences as a driving force. A prediction of this model is that when extensive rearrangements of euchromatin have been facilitated by heterochromatin, genomes will be characterized by tandemly repeated sequences that have actively changed chromosomal fields by intragenomic movement. Alternatively, it is proposed that in conservative chromosomal lineage each class of tandemly repeated sequences will be restricted to a specific chromosomal field. To provide baseline data to test this model we exami...
Wallner B, Vogl C, Shukla P, Burgstaller JP, Druml T, Brem G.The paternally inherited Y chromosome displays the population genetic history of males. While modern domestic horses (Equus caballus) exhibit abundant diversity within maternally inherited mitochondrial DNA, no significant Y-chromosomal sequence diversity has been detected. We used high throughput sequencing technology to identify the first polymorphic Y-chromosomal markers useful for tracing paternal lines. The nucleotide variability of the modern horse Y chromosome is extremely low, resulting in six haplotypes (HT), all clearly distinct from the Przewalski horse (E. przewalskii). The most wi...
Mach N, Foury A, Kittelmann S, Reigner F, Moroldo M, Ballester M, Esquerré D, Rivière J, Sallé G, Gérard P, Moisan MP, Lansade L.Weaning has been described as one of the most stressful events in the life of horses. Given the importance of the interaction between the gut-brain axis and gut microbiota under stress, we evaluated (i) the effect of two different weaning methods on the composition of gut microbiota across time and (ii) how the shifts of gut microbiota composition after weaning affect the host. A total of 34 foals were randomly subjected to a progressive (P) or an abrupt (A) weaning method. In the P method, mares were separated from foals at progressively increasing intervals every day, starting from five min ...
Ezashi T, Yuan Y, Roberts RM.This review deals with the latest advances in the study of embryonic stem cells (ESC) and induced pluripotent stem cells (iPSC) from domesticated species, with a focus on pigs, cattle, sheep, goats, horses, cats, and dogs. Whereas the derivation of fully pluripotent ESC from these species has proved slow, reprogramming of somatic cells to iPSC has been more straightforward. However, most of these iPSC depend on the continued expression of the introduced transgenes, a major drawback to their utility. The persistent failure in generating ESC and the dependency of iPSC on ectopic genes probably s...
Forrester NL, Wertheim JO, Dugan VG, Auguste AJ, Lin D, Adams AP, Chen R, Gorchakov R, Leal G, Estrada-Franco JG, Pandya J, Halpin RA, Hari K, Jain R....Venezuelan equine encephalitis (VEE) complex alphaviruses are important re-emerging arboviruses that cause life-threatening disease in equids during epizootics as well as spillover human infections. We conducted a comprehensive analysis of VEE complex alphaviruses by sequencing the genomes of 94 strains and performing phylogenetic analyses of 130 isolates using complete open reading frames for the nonstructural and structural polyproteins. Our analyses confirmed purifying selection as a major mechanism influencing the evolution of these viruses as well as a confounding factor in molecular cloc...
Su TW, Choi I, Feng J, Huang K, McLeod E, Ozcan A.We report the discovery of an entirely new three-dimensional (3D) swimming pattern observed in human and horse sperms. This motion is in the form of 'chiral ribbons', where the planar swing of the sperm head occurs on an osculating plane creating in some cases a helical ribbon and in some others a twisted ribbon. The latter, i.e., the twisted ribbon trajectory, also defines a minimal surface, exhibiting zero mean curvature for all the points on its surface. These chiral ribbon swimming patterns cannot be represented or understood by already known patterns of sperms or other micro-swimmers. The...
Iacono E, Brunori L, Pirrone A, Pagliaro PP, Ricci F, Tazzari PL, Merlo B.Mesenchymal stem cells (MSCs) have been derived from multiple sources of the horse including umbilical cord blood (UCB) and amnion. This work aimed to identify and characterize stem cells from equine amniotic fluid (AF), CB and Wharton's Jelly (WJ). Samples were obtained from 13 mares at labour. AF and CB cells were isolated by centrifugation, while WJ was prepared by incubating with an enzymatic solution for 2 h. All cell lines were cultured in DMEM/TCM199 plus fetal bovine serum. Fibroblast-like cells were observed in 7/10 (70%) AF, 6/8 (75%) CB and 8/12 (66.7%) WJ samples. Statistically ...
McCue ME, Valberg SJ, Miller MB, Wade C, DiMauro S, Akman HO, Mickelson JR.Polysaccharide storage myopathy (PSSM) is a novel glycogenosis in horses characterized by abnormal glycogen accumulation in skeletal muscle and muscle damage with exertion. It is unlike glycogen storage diseases resulting from known defects in glycogenolysis, glycolysis, and glycogen synthesis that have been described in humans and domestic animals. A genome-wide association identified GYS1, encoding skeletal muscle glycogen synthase (GS), as a candidate gene for PSSM. DNA sequence analysis revealed a mutation resulting in an arginine-to-histidine substitution in a highly conserved region of G...
de Jonge N, Carlsen B, Christensen MH, Pertoldi C, Nielsen JL.The gut microbiome plays a critical role in many aspects of host life, and the microbial community composition is heavily influenced by the prevailing conditions in the gut environment. Community composition has been suggested to have large implications for conservation efforts, and gut health has become of interest for optimizing animal care in captivity. In this study, we explore the gut microbiome of a wide range of animals in the context of conservation biology. The composition of the gut microbial community of 54 mammalian animal species was investigated using 16S rRNA gene amplicon seque...
Klymiuk MC, Balz N, Elashry MI, Heimann M, Wenisch S, Arnhold S.Mesenchymal stem cells are used for different therapeutic approaches, e.g. for osteoarthritis, lesions of the tendon as well as for bone defects. Current research on the mechanism of stem cells on the repair of damaged tissue suggest an important role of a cell-to-cell communication through secreted extracellular vesicles, mainly represented by exosomes. To enhance the scarce knowledge on the functional role of exosomes we compared as a first step different techniques to isolate and identify exosomes from the supernatant of equine adipose derived mesenchymal stem cells for further characteriza...
Janečka JE, Davis BW, Ghosh S, Paria N, Das PJ, Orlando L, Schubert M, Nielsen MK, Stout TAE, Brashear W, Li G, Johnson CD, Metz RP, Zadjali AMA....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 transp...
Hidaka C, Goodrich LR, Chen CT, Warren RF, Crystal RG, Nixon AJ.Cartilage has a limited capacity to heal. Although chondrocyte transplantation is a useful therapeutic strategy, the repair process can be lengthy. Previously we have shown that over expression of bone morphogenetic protein-7 (BMP-7) in chondrocytes by adenovirus-mediated gene transfer leads to increased matrix synthesis and cartilage-like tissue formation in vitro. In this context we hypothesized that implantation of genetically modified chondrocytes expressing BMP-7 would accelerate the formation of hyaline-like repair tissue in an equine model of cartilage defect repair. Methods: Chondrocyt...
