RESUMEN
We here report the results of a mitral valve transcriptome study designed to identify genes and molecular pathways involved in development of congestive heart failure (CHF) following myxomatous mitral valve disease (MMVD) in dogs. The study is focused on a cohort of elderly age-matched dogs (n = 34, age ~ 10 years) from a single breed-Cavalier King Charles Spaniels (CKCS)-with a high incidence of MMVD. The cohort comprises 19 dogs (10â, 9â) without MMVD-associated CHF, and 15 dogs (6â, 9â) with CHF caused by MMVD; i.e., we compare gene expression in breed and age-matched groups of dogs, which only differ with respect to CHF status. We identify 56 genes, which are differentially expressed between the two groups. In this list of genes, we confirm an enrichment of genes related to the TNFß-signaling pathway, extracellular matrix organization, vascular development, and endothelium damage, which also have been identified in previous studies. However, the genes with the greatest difference in expression between the two groups are CNTN3 and MYH1. Both genes encode proteins, which are predicted to have an effect on the contractile activity of myocardial cells, which in turn may have an effect on valvular performance and hemodynamics across the mitral valve. This may result in shear forces with impact on MMVD progression.
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Enfermedades de los Perros , Insuficiencia Cardíaca , Enfermedades de las Válvulas Cardíacas , Humanos , Perros , Animales , Anciano , Niño , Válvula Mitral/metabolismo , Enfermedades de las Válvulas Cardíacas/genética , Enfermedades de las Válvulas Cardíacas/veterinaria , Transcriptoma , Insuficiencia Cardíaca/genética , Insuficiencia Cardíaca/veterinaria , Perfilación de la Expresión Génica , Enfermedades de los Perros/genéticaRESUMEN
Lean meat percentage is a critical production trait in pig breeding systems with direct implications for the sustainability of the industry. In this study, we conducted a genome-wide association study for lean meat percentage using a cohort of 850 Duroc × (Landrace × Yorkshire) crossbred pigs and we identified QTL on SSC3 and SSC18. Based on the predicted effect of imputed variants and using the PigGTEx database of molecular QTL, we prioritized candidate genes and SNPs located within the QTL regions, which may be involved in the regulation of porcine leanness. Our results indicate that a nonsense mutation in ZC3HAV1L on SSC18 has a direct effect on lean meat percentage.
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Genotipo , Polimorfismo de Nucleótido Simple , Sitios de Carácter Cuantitativo , Sus scrofa , Animales , Sus scrofa/genética , Estudio de Asociación del Genoma Completo/veterinaria , Cruzamiento , Carne de CerdoRESUMEN
Post-weaning diarrhea in pigs is a considerable challenge in the pig farming industry due to its effect on animal welfare and production costs, as well as the large volume of antibiotics, which are used to treat diarrhea in pigs after weaning. Previous studies have revealed loci on SSC6 and SSC13 associated with susceptibility to specific diarrhea causing pathogens. This study aimed to identify new genetic loci for resistance to diarrhea based on phenotypic data. In depth clinical characterization of diarrhea was performed in 257 pigs belonging to two herds during the first 14 days post weaning. The daily diarrhea assessments were used for the classification of pigs into case and control groups. Pigs were assigned to case and control groups based only on the incidence of diarrhea in the second week of the study in order to differentiate between differences in etiology. Genome-wide association studies and metabolomics association analysis were performed in order to identify new biological determinants for diarrhea susceptibility. With the present work, we revealed a new locus for diarrhea resistance on SSC16. Furthermore, studies of metabolomics in the same pigs revealed one metabolite associated with diarrhea.
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Diarrea , Enfermedades de los Porcinos , Destete , Animales , Diarrea/veterinaria , Diarrea/genética , Enfermedades de los Porcinos/genética , Estudio de Asociación del Genoma Completo/veterinaria , Porcinos/genética , Sus scrofa/genética , Resistencia a la Enfermedad/genética , MetabolómicaRESUMEN
Cystinuria is a genetic disease that can lead to cystine urolith formation. The English bulldog is the dog breed most frequently affected. In this breed, three missense mutations have been suggested to be associated with cystinuria: c.568A>G and c.2086A>G in SLC3A1 and c.649G>A in SLC7A9. In this study, the occurrence of these three mutations in the Danish population of English bulldogs was investigated. Seventy-one English bulldogs were genotyped using TaqMan assays. The dogs' owners were given questionnaires concerning the medical histories of their dogs. Allele frequencies of 0.40, 0.40, and 0.52 were found for the mutant alleles in the three loci: c.568A>G, c.2086A>G, and c.649G>A, respectively. For both mutations in SLC3A1, a statistically significant association was found between cystinuria and homozygosity for the G allele among male, English bulldogs. For the mutation in SLC7A9, there was no statistically significant association between homozygosity for the mutant allele and cystinuria. Due to high allele frequencies, limited genetic diversity, continued uncertainty about the genetic background of cystinuria, and more severe health problems in the breed, selection based on genetic testing for the mutations in SLC3A1 cannot be recommended in the Danish population of English bulldogs. However, results of the genetic test may be used as a guide to recommend prophylactic treatment.
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Cistinuria , Enfermedades de los Perros , Perros , Masculino , Animales , Cistinuria/genética , Cistinuria/veterinaria , Mutación , Genotipo , Pruebas Genéticas/veterinaria , Dinamarca , Enfermedades de los Perros/genéticaRESUMEN
The contribution of microRNAs (miRNAs) to mRNA post-transcriptional regulation has often been explored by the post hoc selection of downregulated genes and determining whether they harbor binding sites for miRNAs of interest. This approach, however, does not discriminate whether these mRNAs are also downregulated at the transcriptional level. Here, we have characterized the transcriptional and post-transcriptional changes in mRNA expression in two porcine tissues: gluteus medius muscle of fasted and fed Duroc gilts and adipose tissue of lean and obese Duroc-Göttingen minipigs. Exon-intron split analysis of RNA-seq data allowed us to identify downregulated mRNAs with high post-transcriptional signals in fed or obese states, and we assessed whether they harbor binding sites for upregulated miRNAs in any of these two physiological states. We found 26 downregulated mRNAs with high post-transcriptional signals in the muscle of fed gilts and 21 of these were predicted targets of miRNAs upregulated in fed pigs. For adipose tissue, 44 downregulated mRNAs in obese minipigs displayed high post-transcriptional signals, and 25 of these were predicted targets of miRNAs upregulated in the obese state. These results suggest that the contribution of miRNAs to mRNA repression is more prominent in the skeletal muscle system. Finally, we identified several genes that may play relevant roles in the energy homeostasis of the pig skeletal muscle (DKK2 and PDK4) and adipose (SESN3 and ESRRG) tissues. By differentiating transcriptional from post-transcriptional changes in mRNA expression, exon-intron split analysis provides a valuable view of the regulation of gene expression, complementary to canonical differential expression analyses.
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MicroARNs , Enfermedades de los Porcinos , Animales , Exones , Femenino , Perfilación de la Expresión Génica , Regulación de la Expresión Génica , Intrones , MicroARNs/genética , MicroARNs/metabolismo , Músculo Esquelético/metabolismo , Obesidad/genética , ARN Mensajero/genética , ARN Mensajero/metabolismo , Porcinos/genética , Enfermedades de los Porcinos/genética , Porcinos Enanos/genética , Porcinos Enanos/metabolismoRESUMEN
Domestic dogs have been central to life in the North American Arctic for millennia. The ancestors of the Inuit were the first to introduce the widespread usage of dog sledge transportation technology to the Americas, but whether the Inuit adopted local Palaeo-Inuit dogs or introduced a new dog population to the region remains unknown. To test these hypotheses, we generated mitochondrial DNA and geometric morphometric data of skull and dental elements from a total of 922 North American Arctic dogs and wolves spanning over 4500 years. Our analyses revealed that dogs from Inuit sites dating from 2000 BP possess morphological and genetic signatures that distinguish them from earlier Palaeo-Inuit dogs, and identified a novel mitochondrial clade in eastern Siberia and Alaska. The genetic legacy of these Inuit dogs survives today in modern Arctic sledge dogs despite phenotypic differences between archaeological and modern Arctic dogs. Together, our data reveal that Inuit dogs derive from a secondary pre-contact migration of dogs distinct from Palaeo-Inuit dogs, and probably aided the Inuit expansion across the North American Arctic beginning around 1000 BP.
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Distribución Animal , Perros/anatomía & histología , Perros/genética , Genoma Mitocondrial , Fenotipo , Alaska , Animales , Arqueología , Regiones Árticas , Canadá , ADN Antiguo/análisis , ADN Mitocondrial/análisis , Groenlandia , Migración HumanaRESUMEN
Whole transcriptome sequencing (RNA-seq) has become a standard for cataloguing and monitoring RNA populations. One of the main bottlenecks, however, is to correctly identify the different classes of RNAs among the plethora of reconstructed transcripts, particularly those that will be translated (mRNAs) from the class of long non-coding RNAs (lncRNAs). Here, we present FEELnc (FlExible Extraction of LncRNAs), an alignment-free program that accurately annotates lncRNAs based on a Random Forest model trained with general features such as multi k-mer frequencies and relaxed open reading frames. Benchmarking versus five state-of-the-art tools shows that FEELnc achieves similar or better classification performance on GENCODE and NONCODE data sets. The program also provides specific modules that enable the user to fine-tune classification accuracy, to formalize the annotation of lncRNA classes and to identify lncRNAs even in the absence of a training set of non-coding RNAs. We used FEELnc on a real data set comprising 20 canine RNA-seq samples produced by the European LUPA consortium to substantially expand the canine genome annotation to include 10 374 novel lncRNAs and 58 640 mRNA transcripts. FEELnc moves beyond conventional coding potential classifiers by providing a standardized and complete solution for annotating lncRNAs and is freely available at https://github.com/tderrien/FEELnc.
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Genoma , Anotación de Secuencia Molecular/métodos , ARN Largo no Codificante/genética , Programas Informáticos , Transcriptoma , Animales , Benchmarking , Árboles de Decisión , Perros , Regulación de la Expresión Génica , Humanos , Ratones , Anotación de Secuencia Molecular/estadística & datos numéricos , Sistemas de Lectura Abierta , ARN Largo no Codificante/clasificación , ARN Largo no Codificante/metabolismo , ARN Mensajero/clasificación , ARN Mensajero/genética , ARN Mensajero/metabolismo , Análisis de Secuencia de ARNRESUMEN
Ascaris suum is a helminth parasite of pigs closely related to its human counterpart, A. lumbricoides, which infects almost 1 billion people. Ascaris is thought to modulate host immune and inflammatory responses, which may drive immune hyporesponsiveness during chronic infections. Using transcriptomic analysis, we show here that pigs with a chronic A. suum infection have a substantial suppression of inflammatory pathways in the intestinal mucosa, with a broad downregulation of genes encoding cytokines and antigen-processing and costimulatory molecules. A. suum body fluid (ABF) suppressed similar transcriptional pathways in human dendritic cells (DCs) in vitro. DCs exposed to ABF secreted minimal amounts of cytokines and had impaired production of cyclooxygengase-2, altered glucose metabolism, and reduced capacity to induce interferon-gamma production in T cells. Our in vivo and in vitro data provide an insight into mucosal immune modulation during Ascaris infection, and show that A. suum profoundly suppresses immune and inflammatory pathways.
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Ascariasis/patología , Ascaris suum/inmunología , Células Dendríticas/inmunología , Tolerancia Inmunológica , Mucosa Intestinal/patología , Animales , Ascariasis/inmunología , Células Cultivadas , Modelos Animales de Enfermedad , Perfilación de la Expresión Génica , Humanos , Mucosa Intestinal/inmunología , Modelos Biológicos , PorcinosRESUMEN
The aim of this study was to elucidate the relative impact of three phenotypes often used to characterize obesity on perturbation of molecular pathways involved in obesity. The three obesity-related phenotypes are (1) body mass index (BMI), (2) amount of subcutaneous adipose tissue (SATa), and (3) amount of retroperitoneal adipose tissue (RPATa). Although it is generally accepted that increasing amount of RPATa is 'unhealthy', a direct comparison of the relative impact of the three obesity-related phenotypes on gene expression has, to our knowledge, not been performed previously. We have used multiple linear models to analyze altered gene expression of selected obesity-related genes in tissues collected from 19 female pigs phenotypically characterized with respect to the obesity-related phenotypes. Gene expression was assessed by high-throughput qPCR in RNA from liver, skeletal muscle and abdominal adipose tissue. The stringent statistical approach used in the study has increased the power of the analysis compared to the classical approach of analysis in divergent groups of individuals. Our approach led to the identification of key components of cellular pathways that are modulated in the three tissues in association with changes in the three obesity-relevant phenotypes (BMI, SATa and RPATa). The deregulated pathways are involved in biosynthesis and transcript regulation in adipocytes, in lipid transport, lipolysis and metabolism, and in inflammatory responses. Deregulation seemed more comprehensive in liver (23 genes) compared to abdominal adipose tissue (10 genes) and muscle (3 genes). Notably, the study supports the notion that excess amount of intra-abdominal adipose tissue is associated with a greater metabolic disease risk. Our results provide molecular support for this notion by demonstrating that increasing amount of RPATa has a higher impact on perturbation of cellular pathways influencing obesity and obesity-related metabolic traits compared to increase in BMI and amount of SATa.
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Regulación de la Expresión Génica/genética , Grasa Intraabdominal/metabolismo , Obesidad/genética , Grasa Subcutánea/metabolismo , Adipocitos/metabolismo , Adipocitos/patología , Animales , Índice de Masa Corporal , Femenino , Humanos , Grasa Intraabdominal/crecimiento & desarrollo , Hígado/metabolismo , Masculino , Músculo Esquelético/metabolismo , Obesidad/metabolismo , Obesidad/patología , Biosíntesis de Proteínas/genética , Grasa Subcutánea/crecimiento & desarrollo , Porcinos/genética , Porcinos/crecimiento & desarrollo , Porcinos/metabolismoRESUMEN
In human health, there is interest in developing specific diets to reduce body weight. These studies are mainly focused on phenotypic changes induced in blood measurements, i.e., triglycerides, HDL, LDL, and insulin, and on physical changes, i.e., body weight and BMI. To evaluate the biological impact of diet interventions, it is very important to investigate the molecular mechanisms driving the diet-induced phenotypic changes in relevant tissues. However, studying these effects in humans is difficult due to ethical concerns in doing interventions and obtaining tissue samples and good animal models are therefore needed. Göttingen minipigs, a small size obesity prone pig breed, have previously been shown to be a useful translational animal model for metabolic studies. In this study, 16 Göttingen minipig males (2-month old) were submitted to 13 weeks of differential diets to investigate the initial stages of diet-induced metabolic changes. Half of them were fed a high-fat/cholesterol, low-carbohydrate (HFLC) diet, and the other half were fed a low- fat/cholesterol, high-carbohydrate (LFHC) diet. After 13 weeks, the HFLC group weighted less and had dyslipidemia compared to the LFHC group. Liver, pancreas, and adipose tissues were collected at slaughter. Gene expression profiling of 83 metabolism-relevant genes was performed using high-throughput qPCR. In total, 41 genes were deregulated in at least one of the five tissues analyzed, with liver being the most drastically affected tissue. The new knowledge gained in this study could potentially be of value for considering direct modulation of gene expression by nutrient content in the diet.
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Metabolismo de los Hidratos de Carbono/genética , Grasas de la Dieta/metabolismo , Obesidad/metabolismo , Porcinos Enanos/metabolismo , Animales , Colesterol/metabolismo , Dieta con Restricción de Grasas , Humanos , Insulina/metabolismo , Obesidad/genética , Porcinos , Porcinos Enanos/genética , Triglicéridos/metabolismoRESUMEN
BACKGROUND: Taste receptors (TASRs) are essential for the body's recognition of chemical compounds. In the tongue, TASRs sense the sweet and umami and the toxin-related bitter taste thus promoting a particular eating behaviour. Moreover, their relevance in other organs is now becoming evident. In the intestine, they regulate nutrient absorption and gut motility. Upon ligand binding, TASRs activate the appetite-reward circuitry to signal the nervous system and keep body homeostasis. With the aim to identify genetic variation in the swine TASRs and in the genes from the appetite and the reward pathways, we have sequenced the exons of 201 TASRs and appetite-reward genes from 304 pigs belonging to ten breeds, wild boars and to two phenotypically extreme groups from a F2 resource with data on growth and fat deposition. RESULTS: We identified 2,766 coding variants 395 of which were predicted to have a strong impact on protein sequence and function. 334 variants were present in only one breed and at predicted alternative allele frequency (pAAF) ≥ 0.1. The Asian pigs and the wild boars showed the largest proportion of breed specific variants. We also compared the pAAF of the two F2 groups and found that variants in TAS2R39 and CD36 display significant differences suggesting that these genes could influence growth and fat deposition. We developed a 128-variant genotyping assay and confirmed 57 of these variants. CONCLUSIONS: We have identified thousands of variants affecting TASRs as well as genes involved in the appetite and the reward mechanisms. Some of these genes have been already associated to taste preferences, appetite or behaviour in humans and mouse. We have also detected indications of a potential relationship of some of these genes with growth and fat deposition, which could have been caused by changes in taste preferences, appetite or reward and ultimately impact on food intake. A genotyping array with 57 variants in 31 of these genes is now available for genotyping and start elucidating the impact of genetic variation in these genes on pig biology and breeding.
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Apetito/genética , Mutación , Receptores Acoplados a Proteínas G/genética , Gusto/genética , Animales , Cruzamiento , Variación Genética , Fenotipo , Filogenia , Polimorfismo de Nucleótido Simple , Reproducibilidad de los Resultados , Selección Genética , Análisis de Secuencia de ADN , PorcinosRESUMEN
Human obesity and obesity-related diseases (ORD) are growing health problems worldwide and represent a major public health challenge. Most of these diseases are complex conditions, influenced by many genes (including microRNAs) and environmental factors. Many metabolic perturbations are associated with obesity; e.g., low levels of high-density lipoproteins (HDL) are high risk factors of cardiovascular events. A number of genetic, lifestyle, and environmental factors have been shown to contribute to the lowering of HDL-cholesterol. One of these factors is cholesteryl ester transfer protein (CETP) promoting the redistribution of cholesteryl esters, triglycerides, and phospholipids between plasma proteins. Moreover, obesity and ORD are often linked with chronic low-grade inflammation leading to insulin resistance and endothelial and microvascular dysfunctions. The aim of this study was to detect differences in the hepatic expression of genes involved in low-grade inflammation and of obesity- and cholesterol-related microRNAs in two mixed breed populations of pigs (Yorkshire-Göttingen minipig, YM and Duroc-Göttingen minipig, DM) including males and females, with extreme phenotypes for CETP activity levels (designated as CETP-high and CETP-low, respectively). Furthermore, breed and gender differences were also investigated. We found significant difference (P < 0.05) in hepatic expression levels of several mRNAs and microRNAs between the CETP-high and -low groups (C5, IL1RN, IL18, and miR-223-5p); between the two mixed breeds (IL1RAP and miR-140-5p); and between gender (APOA1, IL1RN, and FBLN1). Furthermore, when taking breed into account we show that the transcriptional levels of TNF, miR20a, miR33b, and miR130a differed between the two CETP groups. We conclude that increased CETP activity is accompanied by a modest differential hepatic expression of several microRNAs and inflammatory-related genes. Furthermore, our study demonstrates that when modeling the analysis of expression data, it is important to take gender- and breed-specific effects into account.
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Proteínas de Transferencia de Ésteres de Colesterol/metabolismo , Hígado/metabolismo , MicroARNs/metabolismo , Animales , Femenino , Expresión Génica , Masculino , MicroARNs/genética , Porcinos , Porcinos EnanosRESUMEN
A number of American mink phenotypes display a range of brownish colours. One of these phenotypes, namely American Palomino (b (P) b (P) ) (AP) has been found to be associated with the tyrosinase-related protein 1 (TYRP1) gene by genotyping microsatellite markers in one sire family. Trials for amplifying the genomic DNA and cDNA at the beginning of intron 2 of AP TYRP1 revealed the presence of a large insertion of approximately eight kb. The insertion most likely disrupts different elements necessary for the splicing of intron 2 of the TYRP1 gene. In AP RNAseq data indicate, however, the presence of the wild-type (wt) transcript at very low levels and Western blot reveals three products when using an antibody raised against middle part of the TYRP1 protein. One individual from another brown mink phenotype-commercially named Dawn-was also investigated at the molecular level by long-range PCR and the same size insertion appears to be present. By this we suggest that certain modifiers of TYRP1 would induce different brown colour degradation, which results in at least two different phases of brown.
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Intrones , Visón/genética , Mutagénesis Insercional , Oxidorreductasas/genética , Fenotipo , Animales , Exones , Sitios Genéticos , Marcadores Genéticos , Genotipo , Secuenciación de Nucleótidos de Alto Rendimiento , Oxidorreductasas/metabolismoRESUMEN
Obesity is a world-wide exponentially growing health problem that increases the risk of co-morbidities including metabolic syndrome, pre-diabetes, Type 2 Diabetes Mellitus (T2DM), and cancer. These co-morbidities are all complex conditions constituting a big challenge when searching for susceptibility genes. Identification of relevant genes, which could contribute to an earlier identification of individuals prone to develop diabetes, is urgently needed as many long-term complications can be avoided by preventive measures. Pre-diabetes is mainly associated with hyperglycemia; thus studying this phenotype might provide knowledge on relevant genes implicated in molecular mechanisms underlying pre-diabetes, and contributing to the development of T2DM. In the present study, two groups of pigs with high (HGG, N=6) and low (NGG, N=6) fasting plasma glucose level respectively were selected from a large pig population. Transcriptional levels of seven genes involved in the glucose transporter 4 (GLUT4) translocation pathway were studied by quantitative real-time PCR (qPCR) in diabetes relevant tissues (pancreas, adipose tissue, skeletal muscle, liver and kidney). Three of the genes, TBC (Tre-2, BUB2, CDC16) 1 Domain Family Member 4 (TBC1D4), insulin receptor and GLUT4 showed altered expression in some of the tissues. The expression pattern observed is in agreement with what has previously been reported in pre-diabetic humans confirming the pre-diabetic status of our pigs. Moreover, a novel isoform of TBC1D4 was detected by Western blotting using protein extracted from pancreas. The expression level of this novel isoform was further verified by qPCR in all tissues, showing the highest expression in the pancreas.
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Diabetes Mellitus Tipo 2/metabolismo , Transportador de Glucosa de Tipo 4/metabolismo , Estado Prediabético/metabolismo , Receptor de Insulina/metabolismo , Animales , Diabetes Mellitus Tipo 2/genética , Femenino , Proteínas Activadoras de GTPasa/genética , Expresión Génica , Transportador de Glucosa de Tipo 4/genética , Riñón/metabolismo , Hígado/metabolismo , Masculino , Especificidad de Órganos , Estado Prediabético/genética , Isoformas de Proteínas/genética , Isoformas de Proteínas/metabolismo , Receptor de Insulina/genética , Sus scrofaRESUMEN
BACKGROUND: Staphylococcus aureus is an important human opportunistic pathogen residing on skin and mucosae of healthy people. Pigs have been identified as a source of human colonization and infection with methicillin-resistant Staphylococcus aureus (MRSA) and novel measures are needed to control zoonotic transmission. A recent longitudinal study indicated that a minority of pigs characterized by high nasal load and stable carriage may be responsible for the maintenance of S. aureus within farms. The primary objective of the present study was to detect genetic loci associated with nasal carriage of S. aureus in Danish crossbred pigs (Danish Landrace/Yorkshire/Duroc). RESULTS: Fifty-six persistent carriers and 65 non-carriers selected from 15 farms surveyed in the previous longitudinal study were genotyped using Illumina's Porcine SNP60 beadchip. In addition, spa typing was performed on 126 S. aureus isolates from 37 pigs to investigate possible relationships between host and S. aureus genotypes. A single SNP (MARC0099960) on chromosome 12 was found to be associated with nasal carriage of S. aureus at a genome-wide level after permutation testing (p = 0.0497) whereas the association of a neighboring SNP was found to be borderline (p = 0.114). Typing of S. aureus isolates led to detection of 11 spa types belonging to the three main S. aureus clonal complexes (CC) previously described in pigs (CC9, CC30 and CC398). Individual carriers often harbored multiple S. aureus genotypes and the host-pathogen interaction seems to be independent of S. aureus genotype. CONCLUSION: Our results suggest it may be possible to select pigs genetically resistant to S. aureus nasal colonization as a tool to control transmission of livestock-associated MRSA to humans.
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Portador Sano , Estudio de Asociación del Genoma Completo , Nariz/microbiología , Staphylococcus aureus/aislamiento & purificación , Enfermedades de los Porcinos/microbiología , Animales , Dinamarca , Genotipo , Polimorfismo de Nucleótido Simple , Sitios de Carácter Cuantitativo , Staphylococcus aureus/genética , Porcinos , Enfermedades de los Porcinos/epidemiologíaRESUMEN
Domestication of wild boar (Sus scrofa) and subsequent selection have resulted in dramatic phenotypic changes in domestic pigs for a number of traits, including behavior, body composition, reproduction, and coat color. Here we have used whole-genome resequencing to reveal some of the loci that underlie phenotypic evolution in European domestic pigs. Selective sweep analyses revealed strong signatures of selection at three loci harboring quantitative trait loci that explain a considerable part of one of the most characteristic morphological changes in the domestic pig--the elongation of the back and an increased number of vertebrae. The three loci were associated with the NR6A1, PLAG1, and LCORL genes. The latter two have repeatedly been associated with loci controlling stature in other domestic animals and in humans. Most European domestic pigs are homozygous for the same haplotype at these three loci. We found an excess of derived nonsynonymous substitutions in domestic pigs, most likely reflecting both positive selection and relaxed purifying selection after domestication. Our analysis of structural variation revealed four duplications at the KIT locus that were exclusively present in white or white-spotted pigs, carrying the Dominant white, Patch, or Belt alleles. This discovery illustrates how structural changes have contributed to rapid phenotypic evolution in domestic animals and how alleles in domestic animals may evolve by the accumulation of multiple causative mutations as a response to strong directional selection.
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Animales Domésticos/genética , Genoma , Selección Genética , Porcinos/genética , Secuencia de Aminoácidos , Animales , Variaciones en el Número de Copia de ADN , Homocigoto , Datos de Secuencia Molecular , Sitios de Carácter Cuantitativo , Homología de Secuencia de AminoácidoRESUMEN
The dog was the first domesticated animal but it remains uncertain when the domestication process began and whether it occurred just once or multiple times across the Northern Hemisphere. To ascertain the value of modern genetic data to elucidate the origins of dog domestication, we analyzed 49,024 autosomal SNPs in 1,375 dogs (representing 35 breeds) and 19 wolves. After combining our data with previously published data, we contrasted the genetic signatures of 121 breeds with a worldwide archeological assessment of the earliest dog remains. Correlating the earliest archeological dogs with the geographic locations of 14 so-called "ancient" breeds (defined by their genetic differentiation) resulted in a counterintuitive pattern. First, none of the ancient breeds derive from regions where the oldest archeological remains have been found. Second, three of the ancient breeds (Basenjis, Dingoes, and New Guinea Singing Dogs) come from regions outside the natural range of Canis lupus (the dog's wild ancestor) and where dogs were introduced more than 10,000 y after domestication. These results demonstrate that the unifying characteristic among all genetically distinct so-called ancient breeds is a lack of recent admixture with other breeds likely facilitated by geographic and cultural isolation. Furthermore, these genetically distinct ancient breeds only appear so because of their relative isolation, suggesting that studies of modern breeds have yet to shed light on dog origins. We conclude by assessing the limitations of past studies and how next-generation sequencing of modern and ancient individuals may unravel the history of dog domestication.
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Animales Domésticos/genética , Demografía , Perros/genética , Variación Genética , Animales , Arqueología , Análisis por Conglomerados , Perros/fisiología , Filogeografía , Polimorfismo de Nucleótido Simple/genética , Especificidad de la EspecieRESUMEN
BACKGROUND: Annotating mammalian genomes for noncoding RNAs (ncRNAs) is nontrivial since far from all ncRNAs are known and the computational models are resource demanding. Currently, the human genome holds the best mammalian ncRNA annotation, a result of numerous efforts by several groups. However, a more direct strategy is desired for the increasing number of sequenced mammalian genomes of which some, such as the pig, are relevant as disease models and production animals. RESULTS: We present a comprehensive annotation of structured RNAs in the pig genome. Combining sequence and structure similarity search as well as class specific methods, we obtained a conservative set with a total of 3,391 structured RNA loci of which 1,011 and 2,314, respectively, hold strong sequence and structure similarity to structured RNAs in existing databases. The RNA loci cover 139 cis-regulatory element loci, 58 lncRNA loci, 11 conflicts of annotation, and 3,183 ncRNA genes. The ncRNA genes comprise 359 miRNAs, 8 ribozymes, 185 rRNAs, 638 snoRNAs, 1,030 snRNAs, 810 tRNAs and 153 ncRNA genes not belonging to the here fore mentioned classes. When running the pipeline on a local shuffled version of the genome, we obtained no matches at the highest confidence level. Additional analysis of RNA-seq data from a pooled library from 10 different pig tissues added another 165 miRNA loci, yielding an overall annotation of 3,556 structured RNA loci. This annotation represents our best effort at making an automated annotation. To further enhance the reliability, 571 of the 3,556 structured RNAs were manually curated by methods depending on the RNA class while 1,581 were declared as pseudogenes. We further created a multiple alignment of pig against 20 representative vertebrates, from which RNAz predicted 83,859 de novo RNA loci with conserved RNA structures. 528 of the RNAz predictions overlapped with the homology based annotation or novel miRNAs. We further present a substantial synteny analysis which includes 1,004 lineage specific de novo RNA loci and 4 ncRNA loci in the known annotation specific for Laurasiatheria (pig, cow, dolphin, horse, cat, dog, hedgehog). CONCLUSIONS: We have obtained one of the most comprehensive annotations for structured ncRNAs of a mammalian genome, which is likely to play central roles in both health modelling and production. The core annotation is available in Ensembl 70 and the complete annotation is available at http://rth.dk/resources/rnannotator/susscr102/version1.02.
Asunto(s)
Genoma , ARN/metabolismo , Porcinos/genética , Animales , Análisis por Conglomerados , Sitios Genéticos , Humanos , MicroARNs/genética , MicroARNs/metabolismo , ARN/química , ARN/genética , ARN Ribosómico/genética , ARN Ribosómico/metabolismo , ARN Nucleolar Pequeño/genética , ARN Nucleolar Pequeño/metabolismo , ARN no Traducido/genética , ARN no Traducido/metabolismo , Sintenía/genéticaRESUMEN
Two single nucleotide polymorphisms (SNP TXNIP and SNP ARNT), both on chromosome 4, have been reported to be associated with roundworm (Ascaris suum) burden in pigs. In the present study, we selected pigs with two SNP TXNIP genotypes (AA; n = 24 and AB; n = 24), trickle-infected them with A. suum from 8 weeks of age until necropsy 8 weeks later, and tested the hypothesis that pigs with the AA genotype would have higher levels of resistance than pigs of AB genotype. We used different indicators of resistance (worm burden, fecal egg counts (FEC), number of liver white spots and A. suum-specific serum IgG antibody levels). Pigs of the AA genotype had lower mean macroscopic worm burden (2.4 vs 19.3; P = 0.06), lower mean total worm burden (26.5 vs 70.1; P = 0.09) and excreted fewer A. suum eggs at week 8 PI (mean number of eggs/g feces: 238 vs 1259; P = 0.14) than pigs of the AB genotype, as expected based on prior associations. The pigs were also genotyped at another locus (SNP ARNT) which showed a similar trend. This study provides suggestive evidence that resistant pigs may be selected using a genetic marker, TXNIP, and provides further support to the quantitative trait locus on chromosome 4.
Asunto(s)
Ascariasis/veterinaria , Ascaris suum/fisiología , Resistencia a la Enfermedad/genética , Polimorfismo de Nucleótido Simple/genética , Enfermedades de los Porcinos/inmunología , Alelos , Animales , Ascariasis/inmunología , Ascariasis/parasitología , Heces/parasitología , Femenino , Marcadores Genéticos/genética , Genotipo , Hígado/parasitología , Pulmón/parasitología , Masculino , Recuento de Huevos de Parásitos , Conejos , Porcinos , Enfermedades de los Porcinos/parasitologíaRESUMEN
BACKGROUND: Perosomus elumbis (PE) is a congenital defect that has been observed sporadically in Holstein cattle for many years. However, several cases have been reported in recent years and this may indicate an unrecognised spread of a mutant allele in the Holstein population worldwide. Two cases in Danish Holstein calves are reported to provide details on the phenotype. CASE PRESENTATION: Two full-term Holstein calves were born after assisted delivery due to dystocia with breech presentation. External morphological examination indicated that the lumbar, sacral and coccygeal vertebrae were absent and the abdominal region was just present as a floppy sac covered by skin and enclosing the abdominal organs. The hind limbs were hypoplastic with bilateral symmetric arthrogryposis and muscular atrophy. Radiographs, computed tomography scan and necropsy confirmed these findings. The caudal part of the thoracic spinal cord showed myelodysplasia. A range of abdominal organ malformations were found at necropsy. Inbreeding was not found during genealogical examination, but remote shared ancestors were present in the pedigrees. CONCLUSION: The addition of these further cases of PE to the in recent years reported record of cases should draw more attention to this defect in the Holstein breed. PE may be an emerging genetic defect in the Holstein population worldwide and cases should be sampled to enable genetic mapping of the gene possibly underlying the disease. PE cases seem to be associated with a high risk of dystocia due to increased rate of breech presentation.