Genes in horses are segments of DNA that encode the biological instructions necessary for the development, functioning, and reproduction of equine species. These genetic sequences influence a wide range of traits, including coat color, speed, endurance, and susceptibility to diseases. Genetic research in horses focuses on identifying specific genes and genetic markers associated with these traits, as well as understanding the inheritance patterns and genetic diversity within and between horse breeds. Studies in equine genetics contribute to breeding programs, disease prevention strategies, and the overall understanding of horse biology. This page compiles peer-reviewed research studies and scholarly articles that explore the identification, function, and implications of genes in equine health and performance.
Dossa RG, Alperin DC, Hines MT, Hines SA.The CD1 family is a group of non-polymorphic MHC class I-like molecules that present lipid-based antigens to T cells. Previous work in our laboratory demonstrated that cytotoxic T lymphocytes from immune adult horses recognize lipids from the cell wall of an important equine pathogen, Rhodococcus equi. These findings suggest an important role for the equine CD1 antigen presentation system in protective immune responses to microbial pathogens in the horse. In this study, we characterized and mapped the equine CD1 gene cluster. The equine genome was found to contain 13 complete CD1 genes; seven ...
Degroote RL, Hauck SM, Treutlein G, Amann B, Fröhlich KJ, Kremmer E, Merl J, Stangassinger M, Ueffing M, Deeg CA.Autoimmune uveitis is characterized by crossing of blood-retinal barrier (BRB) by autoaggressive immune cells. Equine recurrent uveitis (ERU) is a valuable spontaneous model for autoimmune uveitis and analyses of differentially expressed proteins in ERU unraveled changed protein clusters in target tissues and immune system. Healthy eyes are devoid of leukocytes. In ERU, however, leukocytes enter the inner eye and subsequently destroy it. Molecular mechanisms enabling cell migration through BRB still remain elusive. Previously, we detected decreased talin 1 expression in blood-derived granulocy...
Teijeiro JM, Marini PE.The oviduct is a dynamic organ in which final gamete maturation, fertilization and early embryo development take place. It is considered to be a sterile site; however the mechanism for sterility maintenance is still unknown. S100A7 is an anti-microbial peptide that has been reported in human reproductive tissues such as prostate, testicle, ovary, normal cervical epithelium and sperm. The current work reports the presence of S100A7 in the Fallopian tube and its localization at the apical surface of epithelial cells. For comparison, porcine S100A7 was used for antibody development and search for...
Warmuth VM, Campana MG, Eriksson A, Bower M, Barker G, Manica A.Animal exchange networks have been shown to play an important role in determining gene flow among domestic animal populations. The Silk Road is one of the oldest continuous exchange networks in human history, yet its effectiveness in facilitating animal exchange across large geographical distances and topographically challenging landscapes has never been explicitly studied. Horses are known to have been traded along the Silk Roads; however, extensive movement of horses in connection with other human activities may have obscured the genetic signature of the Silk Roads. To investigate the role o...
Szóstek AZ, Lukasik K, Galvão AM, Ferreira-Dias GM, Skarzynski DJ.The aim of the study was to characterize endometrial mRNA transcription, immunolocalization, and protein expression of interleukin (IL) 1alpha, IL1beta, IL6, and IL1RI, IL1RII, and IL6Ralpha/beta in the course of endometrosis during the estrous cycle. Additionally, the influence of IL1alpha, IL1beta, and IL6 on prostaglandin (PG) secretion and PG synthase mRNA transcription in endometrial tissue during endometrosis was investigated. The endometrial samples were obtained at the early (n = 12), mid- (n = 12), and late (n = 12) luteal phases and at the follicular (n = 12) phase of the estrous cyc...
Boudreaux MK, Humphries DM.Platelet alloantigens in horses may play an important role in the development of neonatal alloimmune thrombocytopenia (NAIT). Objective: The objective of this study was to evaluate genes encoding major platelet glycoproteins within the Equidae family in an effort to identify potential alloantigens. Methods: DNA was isolated from blood samples obtained from Equidae family members, including a Holsteiner-Oldenburg cross, a Quarter horse, a donkey, and a Plains zebra (Equus burchelli). Gene sequences encoding equine platelet membrane glycoproteins IIb, IIIa (integrin subunits αIIb and β3), Ia (...
Hori Y, Ozaki T, Yamada Y, Tozaki T, Kim HS, Takimoto A, Endo M, Manabe N, Inoue-Murayama M, Fujita K.Genetic polymorphisms in genes related to neurotransmitters or hormones affect personality or behavioral traits in many animal species including humans. In domestic animals, the allele frequency of such genes has been reported to be different among breeds and it may account for breed differences in behavior. In this study, we investigated breed differences in horses in the dopamine receptor D4 gene (DRD4), which has been reported to affect horse personality. We collected samples from seven horse breeds including those native to Japan and Korea, and compared the sequence of the DRD4 exon3 regio...
Tully LJ, Murphy AM, Smith RK, Hulin-Curtis SL, Verheyen KL, Price JS.To explore whether genetic susceptibility is a potential risk factor for superficial digital flexor (SDF) tendinopathy in Thoroughbred (TB) racehorses. Objective: To identify informative single nucleotide polymorphisms (SNPs) that capture genetic diversity across a range of candidate genes and to investigate, in a case-control study, their association with SDF tendinopathy in UK National Hunt TB racehorses in training. Methods: Case-control candidate gene association study. Methods: This study used in silico gene assembly and DNA sequencing to screen candidate genes for SNPs. Seven candidate g...
Switonski M, Mankowska M, Salamon S.The melanocortin receptor gene family consists of five single-exon members, which are located on autosomes. Three genes (MC2R, MC4R and MC5R) are syntenic in the human, mouse, cattle and dog genomes, while in the pig, the syntenic group comprises MC1R, MC2R and MC5R. Two genes (MC1R and MC4R) have been extensively studied due to their function in melanogenesis (MC1R) and energy control (MC4R). Conservative organisation of these genes in five mammalian species (human, mouse, cattle, pig and dog), in terms of the encoded amino acid sequence, is higher in the case of MC4R compared to MC1R. Polymo...
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...
Kulbrock M, Lehner S, Metzger J, Ohnesorge B, Distl O.Equine recurrent uveitis (ERU) is a common eye disease affecting up to 3-15% of the horse population. A genome-wide association study (GWAS) using the Illumina equine SNP50 bead chip was performed to identify loci conferring risk to ERU. The sample included a total of 144 German warmblood horses. A GWAS showed a significant single nucleotide polymorphism (SNP) on horse chromosome (ECA) 20 at 49.3 Mb, with IL-17A and IL-17F being the closest genes. This locus explained a fraction of 23% of the phenotypic variance for ERU. A GWAS taking into account the severity of ERU, revealed a SNP on ECA18 n...
Ball BA, Scoggin KE, Troedsson MH, Squires EL.Biological effects of prostaglandin E2 are mediated via one of four receptors designated EP1, EP2, EP3 and EP4 which are encoded by separate genes. In general, EP1 and EP3 induce smooth muscle contraction whereas EP2 and EP4 induce smooth muscle relaxation. The objective of the current study was to characterize the expression of the genes for PGE2 receptors (EP2 and EP4) in the horse oviduct based upon immunohistochemistry (IHC) and quantitative PCR (qPCR). Oviductal tissue was collected from mares at estrus (n=5), at 5 days post-ovulation (n=4), and from prepubertal mares (n=5). Isthmic and a...
Cwiklinski K, Merga JY, Lake SL, Hartley C, Matthews JB, Paterson S, Hodgkinson JE.Clade V nematodes comprise several parasitic species that include the cyathostomins, primary helminth pathogens of horses. Next generation transcriptome datasets are available for eight parasitic clade V nematodes, although no equine parasites are included in this group. Here, we report next generation transcriptome sequencing analysis for the common cyathostomin species, Cylicostephanus goldi. A cDNA library was generated from RNA extracted from 17 C. goldi male and female adult parasites. Following sequencing using a 454 GS FLX pyrosequencer, a total of 475,215 sequencing reads were generate...
Schauer SN, Sontakke SD, Watson ED, Esteves CL, Donadeu FX.Previous evidence from in vitro studies suggests specific roles for a subset of miRNAs, including miR-21, miR-23a, miR-145, miR-503, miR-224, miR-383, miR-378, miR-132, and miR-212, in regulating ovarian follicle development. The objective of this study was to determine changes in the levels of these miRNAs in relation to follicle selection, maturation, and ovulation in the monovular equine ovary. In Experiment 1, follicular fluid was aspirated during ovulatory cycles from the dominant (DO) and largest subordinate (S) follicles of an ovulatory wave and the dominant (DA) follicle of a mid-cycle...
Coleman SJ, Zeng Z, Hestand MS, Liu J, Macleod JN.Sequencing of equine mRNA (RNA-seq) identified 428 putative transcripts which do not map to any previously annotated or predicted horse genes. Most of these encode the equine homologs of known protein-coding genes described in other species, yet the potential exists to identify novel and perhaps equine-specific gene structures. A set of 36 transcripts were prioritized for further study by filtering for levels of expression (depth of RNA-seq read coverage), distance from annotated features in the equine genome, the number of putative exons, and patterns of gene expression between tissues. From ...
Ninomiya S, Anjiki A, Nishide Y, Mori M, Deguchi Y, Satoh T.In stabled horses, behavioral responses to frustration are often observed, especially around feeding time. These behavioral responses are a useful indicator of their welfare. In this study, we investigated the association between this behavioral indicator and DRD4 gene polymorphisms in stabled horses. Twenty one horses housed in two stables were used. The horses were observed for approximately 4 h around feeding over three or more days using focal-sampling and instantaneous-sampling. Horses were genotyped for the A-G substitution in the DRD4 gene. The effects of the A-G substitution (with or w...
Watts AE, Ackerman-Yost JC, Nixon AJ.To compare in vitro three-dimensional (3D) culture systems that model chondrogenesis of bone marrow-derived mesenchymal stem cells (MSCs). Methods: MSCs from five horses 2-3 years of age were consolidated in fibrin 0.3% alginate, 1.2% alginate, 2.5×10(5) cell pellets, 5×10(5) cell pellets, and 2% agarose, and maintained in chondrogenic medium with supplemental TGF-β1 for 4 weeks. Pellets and media were tested at days 1, 14, and 28 for gene expression of markers of chondrogenic maturation and hypertrophy (ACAN, COL2B, COL10, SOX9, 18S), and evaluated by histology (hematoxylin and eosin, Tolu...
Pawlak EA, Geor RJ, Watts MR, Black SJ, Johnson PJ, Belknap JK.Hypoxia-inducible factor-1α (HIF-1A) is an important protein in the regulation/induction of many genes in the cellular and tissue response to hypoxia and a central mediator in inflammatory signalling. As both hypoxia and inflammatory events are purported to occur in the lamellar epidermis in sepsis-related laminitis in the equid, HIF-1A may play a central role in this disease process. Objective: To assess the regulation of HIF-1A and HIF-1A-related genes in the equine keratinocyte in vitro and in the lamellar tissue of horses with sepsis-related laminitis. Methods: In vivo and in vitro experi...
Teixeira RB, Rendahl AK, Anderson SM, Mickelson JR, Sigler D, Buchanan BR, Coleman RJ, McCue ME.Both graying and melanoma formation in horses have recently been linked to a duplication in the STX17 gene. This duplication, as well as a mutation in the ASIP gene that increases MC1R pathway signaling, affects melanoma risk and severity in gray horses. Objective: To determine if melanoma susceptibility in gray Quarter Horses (QH) is lower than gray horses from other breeds because of decreased MC1R signaling resulting from a high incidence of the MC1R chestnut coat color allele in the QH population. Methods: A total of 335 gray QH with and without dermal melanomas. Methods: Blood or hair roo...
Metzger J, Philipp U, Lopes MS, da Camara Machado A, Felicetti M, Silvestrelli M, Distl O.Copy number variants (CNVs) have been shown to play an important role in genetic diversity of mammals and in the development of many complex phenotypic traits. The aim of this study was to perform a standard comparative evaluation of CNVs in horses using three different CNV detection programs and to identify genomic regions associated with body size in horses. Results: Analysis was performed using the Illumina Equine SNP50 genotyping beadchip for 854 horses. CNVs were detected by three different algorithms, CNVPartition, PennCNV and QuantiSNP. Comparative analysis revealed 50 CNVs that affecte...
Zabek T, Golonka P, Fornal A, Semik E.Genetic polymorphism of IHH gene were investigated in Angloarabian, Polish Coldblood and Polish Halfbred horses with the inclusion of a group of Polish Halfbreds affected by osteochondrosis. IHH is a good candidate gene for association study of developmental disorders mainly affecting skeleton development. DNA sequence spanning IHH gene annotated in the horse genome and its putative promoter were investigated using SANGER sequencing. Analysis of genetic variability at polymorphic sites in the IHH gene body and the promoter region confirmed genetic differences between warmblood and coldblood ho...
Vannucci FA, Kelley MR, Gebhart CJ.Lawsonia intracellularis is an obligate intracellular bacterium and the causative agent of proliferative enteropathy (PE). The disease is endemic in pigs, emerging in horses and has also been reported in a variety of other animal species, including nonhuman primates. Comparing the whole genome sequences of a homologous porcine L. intracellularis isolate cultivated for 10 and 60 passages in vitro, we identified a 18-kb prophage-associated genomic island in the passage 10 (pathogenic variant) that was lost in the passage 60 (non-pathogenic variant). This chromosomal island comprises 15 genes dow...
Hjertner B, Olofsson KM, Lindberg R, Fuxler L, Fossum C.There is accumulating evidence for the involvement of pro-inflammatory cytokines associated with a T helper 17 response in intestinal disorders such as inflammatory bowel disease (IBD) in humans. The involvement of interleukin (IL)-17 or IL-23 in equine IBD has not been studied and most gene expression studies in the equine intestine have been limited to the use of a single non-validated reference gene. In this study, expression of the reference gene candidates β2 microglobulin (β2M), glyceraldehyde 3-phosphate dehydrogenase (GAPDH), histone H2A type 1, hypoxanthine-guanine phosphoribosyltra...
Detournay O, Morrison DA, Wagner B, Zarnegar B, Wattrang E.This study aimed at identifying all of the type I interferon (IFN) genes of the horse and at monitoring their expression in equine cells on in vitro induction. We identified 32 putative type I IFN loci on horse chromosome 23 and an unplaced genomic scaffold. A phylogentic analysis characterized these into 8 different type I IFN classes, that is, putative functional genes for 6 IFN-α, 4 IFN-β, 8 IFN-ω (plus 4 pseudogenes), 3 IFN-δ (plus 1 pseudogene), 1 IFN-κ and 1 IFN-ε, plus 1 IFN-ν pseudogene, and 3 loci belonging to what has previously been called IFN-αω. Our analyses indicate that...
Futas J, Horin P.Natural killer (NK) cells have important functions in immunity. NK recognition in mammals can be mediated through killer cell immunoglobulin-like receptors (KIR) and/or killer cell lectin-like Ly49 receptors. Genes encoding highly variable NK cell receptors (NKR) represent rapidly evolving genomic regions. No single conservative model of NKR genes was observed in mammals. Single-copy low polymorphic NKR genes present in one mammalian species may expand into highly polymorphic multigene families in other species. In contrast to other non-rodent mammals, multiple Ly49-like genes appear to exist ...
Vance SJ, McDonald RE, Cooper A, Kennedy MW, Smith BO.Latherin is an intrinsically surfactant protein of ~23 kDa found in the sweat and saliva of horses. Its function is probably to enhance the translocation of sweat water from the skin to the surface of the pelt for evaporative cooling. Its role in saliva may be to enhance the wetting, softening and maceration of the dry, fibrous food for which equines are adapted. Latherin is unusual in its relatively high content of aliphatic amino acids (~25% leucines) that might contribute to its surfactant properties. Latherin is related to the palate, lung, and nasal epithelium carcinoma-associated protein...
Kachroo P, Ivanov I, Seabury AG, Liu M, Chowdhary BP, Cohen ND.Rhodococcus equi is an intracellular bacterium primarily known as an equine pathogen that infects young foals causing a pyogranulomatuous pneumonia. The molecular mechanisms mediating the immune response of foals to R. equi are not fully elucidated. Hence, global genomic high-throughput tools like gene expression microarrays might identify age-related gene expression signatures and molecular pathways that contribute to the immune mechanisms underlying the inherent susceptibility of foals to disease caused by R. equi. The objectives of this study were 2-fold: 1) to compare the expression profil...
Vézina Audette R, Lavoie-Lamoureux A, Lavoie JP, Laverty S.Osteoarthritis (OA) is a degenerative disease of joint tissues that causes articular cartilage erosion, osteophytosis and loss of function due to pain. Inflammation and inflammatory cytokines in synovial fluid (SF) contribute to OA progression. Intra-articular (IA) injections of multipotent mesenchymal stromal cells (MSCs) are employed to treat OA in both humans and animals. MSCs secrete paracrine pro-inflammatory and anabolic signaling molecules that promote tissue repair. The objective of this study was to investigate the effects of OASF on the gene expression of paracrine signaling molecule...
Guzeloglu A, Atli MO, Kurar E, Kayis SA, Handler J, Semacan A, Aslan S.The aims of the present study were to elucidate the expression profiles of leukotriene (LT) pathway mRNA transcription and to determine the possible interaction of LT and prostaglandin (PTG) pathways genes in equine endometrium during the estrous cycle and early pregnancy. Endometrial biopsies were obtained from mares on the day of ovulation (d0), at late diestrous (LD, n = 4), and after luteolysis in the estrus phase (AL, n = 4) of the cycle. Biopsies were also taken on Days 14 (P14; n = 4), 18 (P18, n = 4), and 22 (P22, n = 4) during early pregnancy that were comparable days to cyclic sampli...
Steiner CC, Ryder OA.Prdm9 (Meisetz) is the first speciation gene discovered in vertebrates conferring reproductive isolation. This locus encodes a meiosis-specific histone H3 methyltransferase that specifies meiotic recombination hotspots during gametogenesis. Allelic differences in Prdm9, characterized for a variable number of zinc finger (ZF) domains, have been associated with hybrid sterility in male house mice via spermatogenic failure at the pachytene stage. The mule, a classic example of hybrid sterility in mammals also exhibits a similar spermatogenesis breakdown, making Prdm9 an interesting candidate to e...
Carmona JU, Ríos DL, López C, Álvarez ME, Pérez JE.Platelet-rich plasma (PRP) preparations are used in horses with osteoarthritis (OA). However, some controversies remain regarding the ideal concentration of platelets and leukocytes to produce an adequate anti-inflammatory and anabolic response in the synovial membrane. The aims of this study were to study the influence of leukoconcentrated platelet-rich gel (Lc-PRG) and leukoreduced platelet-rich gel (Lr-PRG) supernatants on the quantitative expression of some proinflammatory and anabolic genes in equine synovial membrane explants (SMEs) challenged with lipopolysaccharide (LPS). SMEs from six...
François L, Jäderkvist Fegraeus K, Eriksson S, Andersson LS, Tesfayonas YG, Viluma A, Imsland F, Buys N, Mikko S, Lindgren G, Velie BD.Many genes are known to have an influence on conformation and performance traits; however, the role of one gene, Myostatin (MSTN), has been highlighted in recent studies on horses. Myostatin acts as a repressor in the development and regulation of differentiation and proliferative growth of skeletal muscle. Several studies have examined the link between MSTN, conformation, and performance in racing breeds, but no studies have investigated the relationship in Icelandic horses. Icelandic horses, a highly unique breed, are known both for their robust and compact conformation as well as their addi...
Tachibana Y, Nakano Y, Nagaoka K, Kikuchi M, Nambo Y, Haneda S, Matsui M, Miyake Y, Imakawa K.Despite enormous efforts, biochemical and molecular mechanisms associated with equine reproduction, particularly processes of pregnancy establishment, have not been well characterized. Previously, PCR-selected suppression subtraction hybridization analysis was executed to identify unique molecules functioning in the equine endometrium during periods of pregnancy establishment, and granzyme B (GZMB) cDNA was found in the pregnant endometrial cDNA library. Because GZMB is produced from natural killer (NK) cells, endometrial expression of GZMB and immune-related transcripts were characterized in ...
Cwiklinski K, Merga JY, Lake SL, Hartley C, Matthews JB, Paterson S, Hodgkinson JE.Clade V nematodes comprise several parasitic species that include the cyathostomins, primary helminth pathogens of horses. Next generation transcriptome datasets are available for eight parasitic clade V nematodes, although no equine parasites are included in this group. Here, we report next generation transcriptome sequencing analysis for the common cyathostomin species, Cylicostephanus goldi. A cDNA library was generated from RNA extracted from 17 C. goldi male and female adult parasites. Following sequencing using a 454 GS FLX pyrosequencer, a total of 475,215 sequencing reads were generate...
Wong KS, Cheung HW, Szeto CWL, Tsang CYN, Wan TSM, Ho ENM.Illicit administration of transgene into horses is a form of gene doping that has been a key concern in equine sports. The large number of potential performance-enhancing transgenes has demanded a cost-effective and reliable detection method. Multiplex qPCR is a relevant technique, but the cross-talking between fluorophores and high background noise limits the method sensitivity and specificity. This study reports a simpler multiplexing approach by using the same fluorophore for four hydrolysis probes each targeting one of the four transgenes: human growth hormone, insulin-like growth factor 1...
Lee EJ, Raudsepp T, Kata SR, Adelson D, Womack JE, Skow LC, Chowdhary BP.Comparative genomics has served as a backbone for the rapid development of gene maps in domesticated animals. The integration of this approach with radiation hybrid (RH) analysis provides one of the most direct ways to obtain physically ordered comparative maps across evolutionarily diverged species. We herein report the development of a detailed RH and comparative map for horse chromosome 17 (ECA17). With markers distributed at an average interval of every 1.4 Mb, the map is currently the most informative among the equine chromosomes. It comprises 75 markers (56 genes and 19 microsatellites),...
Libardoni F, Vielmo A, Farias L, Matter LB, Pötter L, Spilki FR, de Vargas AC.Strangles is the main upper respiratory tract disease of horses. There are currently no studies on the changes in alleles of the M protein gene (seM) in Brazilian isolates of Streptococcus equi ssp. equi (S. equi). This study aimed to analyze and differentiate molecularly S. equi isolates from equine clinical specimens from southern Brazil, between 1994 and 2010. seM alleles were analyzed in 47 isolates of S. equi obtained from clinical cases of strangles (15 Thoroughbred horses, 29 Crioulo breed horses and three Brasileiro de Hipismo--BH). seM alleles characterization was performed by compari...
Jasiński T, Zdrojkowski Ł, Ferreira-Dias G, Kautz E, Juszczuk-Kubiak E, Domino M.Endometrosis is a frequently occurring disease decreasing mares' fertility. Thus, it is an important disease of the endometrium associated with epithelial and stromal cell alterations, endometrium gland degeneration and periglandular fibrosis. Multiple degenerative changes are found in uterine mucosa, the endometrium. However, their pathogenesis is not well known. It is thought that nuclear factor-κB (NF-κB), a cell metabolism regulator, and its activation pathways take part in it. The transcription of the profibrotic pathway genes of the NF-κB in fibrotic endometria differed between the fo...
Lawless SP, Cohen ND, Lawhon SD, Chamoun-Emanuelli AM, Wu J, Rivera-Vélez A, Weeks BR, Whitfield-Cargile CM.Distal limb wounds are common injuries sustained by horses and their healing is fraught with complications due to equine anatomy, prevalence of infection, and challenges associated with wound management. Gallium is a semi-metallic element that has been shown to possess antimicrobial properties and aid in wound healing in various preclinical models. The effects of Gallium have not been studied in equine wound healing. Therefore, the objective of this study was to compare healing rates between gallium-treated and untreated wounds of equine distal limbs and to demonstrate the antimicrobial effect...
Mignot CC, Pirottin D, Farnir F, de Moffarts B, Molitor C, Lekeux P, Art T.The effects of strenuous exercise and ex vivo stimulation of TLR3 and TLR4 pathways on the expression of six inflammatory genes in equine pulmonary leukocytes were investigated. The genes tested were interferon-beta (IFN-β), interleukin-1-beta (IL-1β), interleukin-6 (IL-6), interferon gamma-induced protein 10 (IP-10), chemokine (c-c motif) ligand 5 (RANTES) and tumor necrosis factor-alpha (TNF-α). We hypothesized that strenuous exercise would modulate basal gene expression on one hand and modulate the response to bacterial lipopolysaccharide (LPS) and to polyinosinic:polycytidylic acid (Pol...
Ren X, Liu Y, Zhao Y, Li B, Bai D, Bou G, Zhang X, Du M, Wang X, Bou T, Shen Y, Dugarjaviin M.Interspecific hybridization often shows negative effects on hybrids. However, only a few multicellular species, limited to a handful of plants and animals, have shown partial genetic mechanisms by which hybridization leads to low fitness in hybrids. Here, to explore the outcome of combining the two genomes of a horse and donkey, we analyzed the whole-genome sequences from an parent-offspring trio using Illumina platforms. We generated 41.39× and 46.21× coverage sequences for the horse and mule, respectively. For the donkey, a 40.38× coverage sequence was generated and stored in our laborat...
Cassimeris L, Engiles JB, Galantino-Homer H.Supporting Limb Laminitis (SLL) is a painful and crippling secondary complication of orthopedic injuries and infections in horses, often resulting in euthanasia. SLL causes structural alterations and inflammation of the interdigitating layers of specialized epidermal and dermal tissues, the lamellae, which suspend the equine distal phalanx from the hoof capsule. Activation of the interleukin-17A (IL-17A)-dependent inflammatory pathway is an epidermal stress response that contributes to physiologic cutaneous wound healing as well as pathological skin conditions. As a first test of the hypothesi...
Martoriati A, Lalmanach AC, Goudet G, Gérard N.A growing body of evidence suggests that the ovary is a site of inflammatory reactions, and thus, ovarian cells could represent sources and targets of the interleukin-1 (IL-1) system. The aim of the present work was to investigate the expression of IL-1alpha, IL-1beta, IL-1ra, IL-1R1, and IL-1R2 genes in equine cumulus cells and oocytes. Moreover, the influence of IL-1beta on in vitro maturation of cumulus-oocytes complexes (COCs) was examined. COCs were collected using ultrasound-guided follicular puncture in vivo. Oocytes and cumulus cells were isolated from preovulatory and subordinate foll...
Kim DS, Kim DW, Kim MY, Nam SH, Choi SH, Kim RN, Kang A, Kim A, Park HS.A conjoined gene is defined as one formed at the time of transcription by combining at least part of one exon from each of two or more distinct genes that lie on the same chromosome, in the same or opposite orientation, which translate independently into different proteins. We comparatively studied the extent of conjoined genes in thirteen genomes by analyzing the public databases of expressed sequence tags and mRNA sequences using a set of computational tools designed to identify conjoined genes on the same DNA strand or opposite DNA strands of the same genomic locus. The CACG database, avail...
Takai S, Murata N, Kudo R, Narematsu N, Kakuda T, Sasaki Y, Tsubaki S.This report describes the discovery of two new virulence plasmid types from a crossbred foal with Rhodococcus equi pneumonia in Kumamoto died with severe R. equi pneumonia and ulcerative enteritis. R. equi was isolated in large numbers and isolates from the foal were investigated for the presence of virulence-associated 15-17 kDa antigens (VapA) by colony blotting, using the monoclonal antibody 10G5, and by gene coding for VapA by PCR. Plasmid DNAs extracted from the isolates were digested with restriction endonucleases BamHI, EcoRI, EcoT22I, and HindIII. The digestion patterns that resulted d...
Caetano AR, Pomp D, Murray JD, Bowling AT.Polymerase chain reaction primers designed from horse cDNA sequences and from consensus sequences highly conserved in mammalian species were used to amplify markers for synteny mapping 18 equine type I genes. These markers were used to screen a horse-mouse somatic cell hybrid panel (UCDavis SCH). Fourteen primer sets amplified horse-specific fragments, while restriction enzyme digests of PCR products were used to distinguish the fragments amplified from horse and mouse with four primer sets. Synteny assignments were made based on correlation values between each marker tested and other markers ...
Musiał AD, Ropka-Molik K, Piórkowska K, Jaworska J, Stefaniuk-Szmukier M.In horses, the identification of the genetic background of phenotypic variation, especially with regard to performance characteristics and predisposition to effort, has been extensively studied. As α-actinin-3 function is related to the regulation of muscle contraction and cell metabolism, the ACTN3 gene is considered one of the main genetic factors determining muscle strength. The aim of the present study was to assess the genotype distribution of two SNP variants within the equine ACTN3 gene (g.1104G > A and c.2334C > T) across different utility types and horse breeds. The ana...
Morgan R, Keen J, Halligan D, O'Callaghan A, Andrew R, Livingstone D, Abernethie A, Maltese G, Walker B, Hadoke P.Glucocorticoids are potent inhibitors of angiogenesis in the rodent in vivo and in vitro but the mechanism by which this occurs has not been determined. Administration of glucocorticoids is used to treat a number of conditions in horses but the angiogenic response of equine vessels to glucocorticoids and, therefore, the potential role of glucocorticoids in pathogenesis and treatment of equine disease, is unknown. This study addressed the hypothesis that glucocorticoids would be angiostatic both in equine and murine blood vessels.The mouse aortic ring model of angiogenesis was adapted to assess...
Tully LJ, Murphy AM, Smith RK, Hulin-Curtis SL, Verheyen KL, Price JS.To explore whether genetic susceptibility is a potential risk factor for superficial digital flexor (SDF) tendinopathy in Thoroughbred (TB) racehorses. Objective: To identify informative single nucleotide polymorphisms (SNPs) that capture genetic diversity across a range of candidate genes and to investigate, in a case-control study, their association with SDF tendinopathy in UK National Hunt TB racehorses in training. Methods: Case-control candidate gene association study. Methods: This study used in silico gene assembly and DNA sequencing to screen candidate genes for SNPs. Seven candidate g...
Noschka E, Vandenplas ML, Hurley DJ, Moore JN.The results of recent studies indicate that inflammatory responses occurring in the early stages of equine laminitis lead to downstream events that eventually result in failure of the bond between the hoof wall and the distal phalanx. In order to gain further insights into the molecular mechanisms involved in the development of laminitis, an equine-specific cDNA microarray consisting of transcripts for more that 3000 genes was used to assess temporal changes in gene expression in laminar tissues at 1.5, 3 and 12 h after administration of either a laminitis-inducing agent (black walnut heartwoo...
Asadollahpour Nanaei H, Ayatollahi Mehrgardi A, Esmailizadeh A.Equine athletes have a genetic heritage that has been evolved for millions of years, which provides an opportunity to study the genetics of locomotion pattern and performance in mammals. The Hanoverian, a breed originating in Germany, is arguably among the most athletic of horse breeds, as well as possessing a balanced character and beautiful appearance. Here, we compared the whole genomes of Hanoverian with three other horse breeds (Akhal-Teke, Franches-Montagnes, and Standardbred), using the fixation index (Fst) and cross-population composite likelihood ratio (XP-CLR) methods for testing the...
Aleman M, Finno CJ, Weich K, Penedo MCT.The carrier status of lavender foal syndrome (LFS), cerebellar abiotrophy (CA), severe combined immunodeficiency (SCID), and occipitoatlantoaxial malformation (OAAM1) in foals with juvenile idiopathic epilepsy (JIE) is unknown. Objective: To determine the carrier status of LFS, CA, SCID, and OAAM1 in foals with JIE. Methods: Ten foals with JIE. Methods: Archived DNA samples were tested for known genetic mutations causing LFS, CA, SCID, and OAAM1. The inclusion criteria consisted of having been diagnosed with JIE by ruling out other causes of seizures in foals and supported by electroencephalog...
Díaz S, Giovambattista G, Dulout FN, Peral-García P.Genetic variation in the equine leucocyte antigen-DRB (ELA-DRB) second exon was investigated using polymerase chain reaction (PCR) amplification, restriction fragment length polymorphism (RFLP) of PCR products (PCR-RFLP) and deoxyribonucleic acid (DNA) sequencing. Eight distinct PCR-RFLP patterns could be identified in the studied Argentine Creole (AC) horses. The number of observed patterns per individual ranged from four to six, thus confirming the presence of multiple DRB copies in AC horses. Three PCR-RFLP alleles and three new sequences were identified. The estimated rates of synonymous a...
Dranchak PK, Valberg SJ, Onan GW, Gallant EM, Binns MM, Swinburne JE, Mickelson JR.To determine whether there was genetic linkage between the recurrent exertional rhabdomyolysis (RER) trait in Thoroughbred horse pedigrees and DNA markers in genes (the sarcoplasmic reticulum calcium release channel [RYR1] gene, the sarcoplasmic reticulum calcium ATPase [ATP2A1] gene, and the transverse tubule dihydropyridine receptor-voltage sensor [CACNA1S] gene) that are important in myoplasmic calcium regulation. Methods: 34 horses in the University of Minnesota RER resource herd and 62 Thoroughbreds from 3 families of Thoroughbreds outside of the university in which RER-affected status wa...
Diel de Amorim M, Bramer SA, Rajamanickam GD, Klein C, Card C.Our understanding of the temporal changes in endometrial and luteal gene transcripts related to the actions of oxytocin and prostaglandin during early equine pregnancy is incomplete. Additionally, the role of oxytocinase, also known as Leucyl-cystinyl aminopeptidase (LNPEP), during early pregnancy in mares has not been previously investigated. Luteal and endometrial biopsies were obtained on Day (D)8, D10, D12 and D15 post-ovulation in pregnant (PREG) and diestrus (DIEST) mares for real-time qPCR. Differences in endometrial gene expression occurred over time in: SLC2A4, SLC2A1, PTGES, OXTR and...
Young AE, Bower LP, Affolter VK, De Cock HE, Ferraro GL, Bannasch DL.Chronic progressive lymphedema (CPL) is a debilitating condition identified in Clydesdales, Shires and Belgian draft horses and results in progressive swelling of the lower legs associated with the development of thick skin folds, ulcerations, fibrosis and marked hyperkeratosis. The result is severe discomfort and recurrent secondary infection, often requiring euthanasia. Due to the delayed onset, many horses are bred prior to diagnosis. CPL has only been documented in three related draft horse breeds, suggesting a genetic cause. Determining the molecular basis would enable owners to test hors...
Giesecke K, Sieme H, Distl O.Stallion fertility is of high economic importance for the horse industry. The discovery of molecular mechanisms affecting fertility will be facilitated by the horse genome assembly and the development of novel tools for analysing complex genetic traits. Genetic markers in candidate genes, such as CRISP3, SPATA1 and INHBA, in breeding stallions have been associated with pregnancy rate per oestrus in mares. This paper reviews candidate autosomal, X and Y genes for stallion fertility, including genes encoding hormones and their receptors of the hypothalamic-pituitary axis, proteins of the seminal...
Kwasnik M, Gora IM, Rola J, Zmudzinski JF, Rozek W.The phylogenetic analysis of influenza virus is based mainly on the variable hemagglutinin or neuraminidase genes. However, some discrete evolutionary trends might be revealed when more conservative genes are considered. We compared all available in GenBank database full length NS sequences of equine influenza virus including Polish isolates. Four nucleotides at positions A202, A237, T672 and A714 and three amino acids at positions H59, K71 and S216 which are also present in A/eq/Pulawy/2006 and A/eq/Pulawy/2008 may be discriminating for the Florida sublineage. Threonine at position 83 seems t...
Wall GV, Wright IM, Barnardo C, Erasmus BJ, van Staden V, Potgieter AC.African horse sickness virus (AHSV) non-structural protein NS4 is a nucleocytoplasmic protein that is expressed in the heart, lung, and spleen of infected horses, binds dsDNA, and colocalizes with promyelocytic leukemia nuclear bodies (PML-NBs). The aim of this study was to investigate the role of AHSV NS4 in viral replication, virulence and the host immune response. Using a reverse genetics-derived virulent strain of AHSV-5 and NS4 deletion mutants, we showed that knockdown of NS4 expression has no impact in cell culture, but results in virus attenuation in infected horses. RNA sequencing (RN...
Scott EY, Penedo MCT, Murray JD, Finno CJ.Equine cerebellar abiotrophy (CA) is a hereditary neurodegenerative disease that affects the Purkinje neurons of the cerebellum and causes ataxia in Arabian foals. Signs of CA are typically first recognized either at birth to any time up to 6 months of age. CA is inherited as an autosomal recessive trait and is associated with a single nucleotide polymorphism (SNP) on equine chromosome 2 (13074277G>A), located in the fourth exon of TOE1 and in proximity to MUTYH on the antisense strand. We hypothesize that unraveling the functional consequences of the CA SNP using RNA-seq will elucidate the m...
