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Subramanian S, Kumar M. The Association between the Abundance of Homozygous Deleterious Variants and the Morbidity of Dog Breeds. BIOLOGY 2024; 13:574. [PMID: 39194512 DOI: 10.3390/biology13080574] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/24/2024] [Revised: 07/26/2024] [Accepted: 07/27/2024] [Indexed: 08/29/2024]
Abstract
It is well known that highly inbred dogs are more prone to diseases than less inbred or outbred dogs. This is because inbreeding increases the load of recessive deleterious variants. Using the genomes of 392 dogs belonging to 83 breeds, we investigated the association between the abundance of homozygous deleterious variants and dog health. We used the number of non-routine veterinary care events for each breed to assess the level of morbidity. Our results revealed a highly significant positive relationship between the number of homozygous deleterious variants located within the runs of homozygosity (RoH) tracts of the breeds and the level of morbidity. The dog breeds with low morbidity had a mean of 87 deleterious SNVs within the RoH, but those with very high morbidity had 187 SNVs. A highly significant correlation was also observed for the loss-of-function (LoF) SNVs within RoH tracts. The dog breeds that required more veterinary care had 2.3 times more homozygous LoF SNVs than those that required less veterinary care (112 vs. 50). The results of this study could be useful for understanding the disease burden on breed dogs and as a guide for dog breeding programs.
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Affiliation(s)
- Sankar Subramanian
- Centre for Bioinnovation, University of the Sunshine Coast, Sippy Downs, QLD 4556, Australia
- School of Science, Technology, and Engineering, University of the Sunshine Coast, Moreton Bay, QLD 4502, Australia
| | - Manoharan Kumar
- Centre for Tropical Bioinformatics and Molecular Biology, James Cook University, Cairns, QLD 4502, Australia
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2
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Cocostîrc V, Paștiu AI, Pusta DL. An Overview of Canine Inherited Neurological Disorders with Known Causal Variants. Animals (Basel) 2023; 13:3568. [PMID: 38003185 PMCID: PMC10668755 DOI: 10.3390/ani13223568] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/10/2023] [Revised: 11/15/2023] [Accepted: 11/15/2023] [Indexed: 11/26/2023] Open
Abstract
Hereditary neurological conditions documented in dogs encompass congenital, neonatal, and late-onset disorders, along with both progressive and non-progressive forms. In order to identify the causal variant of a disease, the main two approaches are genome-wide investigations and candidate gene investigation. Online Mendelian Inheritance in Animals currently lists 418 Mendelian disorders specific to dogs, of which 355 have their likely causal genetic variant identified. This review aims to summarize the current knowledge on the canine nervous system phenes and their genetic causal variant. It has been noted that the majority of these diseases have an autosomal recessive pattern of inheritance. Additionally, the dog breeds that are more prone to develop such diseases are the Golden Retriever, in which six inherited neurological disorders with a known causal variant have been documented, and the Belgian Shepherd, in which five such disorders have been documented. DNA tests can play a vital role in effectively managing and ultimately eradicating inherited diseases.
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Affiliation(s)
- Vlad Cocostîrc
- Department of Genetics and Hereditary Diseases, Faculty of Veterinary Medicine, University of Agricultural Sciences and Veterinary Medicine Cluj-Napoca, 400372 Cluj-Napoca, Romania; (A.I.P.); (D.L.P.)
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3
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Letko A, Brülisauer F, Häfliger IM, Corr E, Scholes S, Drögemüller C. Loss-of-function variant in the ovine TMCO6 gene in North Country Cheviot sheep with motor neuron disease. Genomics 2023; 115:110689. [PMID: 37488055 DOI: 10.1016/j.ygeno.2023.110689] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/03/2023] [Revised: 06/27/2023] [Accepted: 07/21/2023] [Indexed: 07/26/2023]
Abstract
In North Country Cheviot lambs with early-onset progressive ataxia and motor neuron degeneration, whole-genome sequencing identified a homozygous loss-of-function variant in the ovine transmembrane and coiled-coil domains (TMCO6) gene. The familial recessive form of motor neuron disease in sheep is due to a pathogenic 4 bp deletion leading to a 50% protein truncation that is assumed to result in the absence of a functional TMCO6. This uncharacterised protein is proposed to interact with ubiquilin 1 which is associated with Alzheimer's disease, whereas sporadic forms of amyotrophic lateral sclerosis are caused by variants in UBQLN2. Our findings provide a first spontaneous animal model for TMCO6, which could have implications in the studies of other comparative neurodegenerative diseases. In addition, these results will allow the design of a genetic test to prevent the occurrence of this fatal disease in the affected sheep population.
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Affiliation(s)
- Anna Letko
- Institute of Genetics, Vetsuisse Faculty, University of Bern, Bern 3012, Switzerland.
| | - Franz Brülisauer
- SRUC Veterinary Services, Pentlands Science Park, Bush Estate Loan, Penicuik, Midlothian EH26 0PZ, United Kingdom.
| | - Irene M Häfliger
- Institute of Genetics, Vetsuisse Faculty, University of Bern, Bern 3012, Switzerland.
| | - Eilidh Corr
- SRUC Veterinary Services, Pentlands Science Park, Bush Estate Loan, Penicuik, Midlothian EH26 0PZ, United Kingdom.
| | - Sandra Scholes
- SRUC Veterinary Services, Pentlands Science Park, Bush Estate Loan, Penicuik, Midlothian EH26 0PZ, United Kingdom
| | - Cord Drögemüller
- Institute of Genetics, Vetsuisse Faculty, University of Bern, Bern 3012, Switzerland.
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Mandigers PJJ, Stehling O, Vos-Loohuis M, Van Steenbeek FG, Lill R, Leegwater PA. A novel IBA57 variant is associated with mitochondrial iron-sulfur protein deficiency and necrotizing myelopathy in dogs. Front Genet 2023; 14:1190222. [PMID: 37588046 PMCID: PMC10425596 DOI: 10.3389/fgene.2023.1190222] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/20/2023] [Accepted: 06/27/2023] [Indexed: 08/18/2023] Open
Abstract
Introduction: Hereditary necrotizing myelopathy (HNM) in young Kooiker dogs is characterized by progressive ataxia and paralysis with autosomal recessive inheritance. The basic genetic defect is unknown. We investigated the possible cause by a genome-wide analysis using six affected and 17 unrelated unaffected Kooiker dogs and by functional follow-up studies. Method: The HNM locus was mapped by a case-control study using a dense SNP array and confirmed by linkage analysis of two pedigrees. The gene exons in the critical region were analyzed by next-generation sequencing. The functional effect of the candidate canine IBA57 pathogenic variant was biochemically examined in an established HeLa cell culture model in which the endogenous IBA75 gene product was depleted by RNAi. Results: The basic defect was localized in the centromeric 5 Mb region of canine chromosome 14. The most associated SNP co-segregated fully with HNM and reached an LOD score of 6.1. A candidate pathogenic mutation was found in the iron-sulfur cluster assembly gene IBA57 and led to the amino acid substitution R147W. The expression of human IBA57 harboring the canine R147W exchange could only partially restore the biochemical defects of several mitochondrial [4Fe-4S] proteins upon IBA57 depletion, showing that the mutant protein is functionally impaired. Discussion: Pathogenic variants in human IBA57 cause multiple mitochondrial dysfunction syndrome 3 (MMDS3), a neurodegenerative disorder with distant similarities to HNM. The incomplete functional complementation of IBA57-depleted human cells by IBA57-R147W identifies the DNA mutation in affected Kooiker dogs as the genetic cause of HNM. Our findings further expand the phenotypic spectrum of pathogenic IBA57 variants.
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Affiliation(s)
- Paul J. J. Mandigers
- Expertise Centre of Genetics, Department of Clinical Sciences, Faculty of Veterinary Medicine, Utrecht University, Utrecht, Netherlands
| | - Oliver Stehling
- Institut für Zytobiologie und Zytopathologie and Center for Synthetic Microbiology Synmikro, Philipps-Universität Marburg, Marburg, Germany
| | - Manon Vos-Loohuis
- Expertise Centre of Genetics, Department of Clinical Sciences, Faculty of Veterinary Medicine, Utrecht University, Utrecht, Netherlands
| | - Frank G. Van Steenbeek
- Expertise Centre of Genetics, Department of Clinical Sciences, Faculty of Veterinary Medicine, Utrecht University, Utrecht, Netherlands
| | - Roland Lill
- Institut für Zytobiologie und Zytopathologie and Center for Synthetic Microbiology Synmikro, Philipps-Universität Marburg, Marburg, Germany
| | - Peter A. Leegwater
- Expertise Centre of Genetics, Department of Clinical Sciences, Faculty of Veterinary Medicine, Utrecht University, Utrecht, Netherlands
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Mock ED, Gagestein B, van der Stelt M. Anandamide and other N-acylethanolamines: A class of signaling lipids with therapeutic opportunities. Prog Lipid Res 2023; 89:101194. [PMID: 36150527 DOI: 10.1016/j.plipres.2022.101194] [Citation(s) in RCA: 35] [Impact Index Per Article: 35.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/20/2022] [Revised: 09/13/2022] [Accepted: 09/15/2022] [Indexed: 01/18/2023]
Abstract
N-acylethanolamines (NAEs), including N-palmitoylethanolamine (PEA), N-oleoylethanolamine (OEA), N-arachidonoylethanolamine (AEA, anandamide), N-docosahexaenoylethanolamine (DHEA, synaptamide) and their oxygenated metabolites are a lipid messenger family with numerous functions in health and disease, including inflammation, anxiety and energy metabolism. The NAEs exert their signaling role through activation of various G protein-coupled receptors (cannabinoid CB1 and CB2 receptors, GPR55, GPR110, GPR119), ion channels (TRPV1) and nuclear receptors (PPAR-α and PPAR-γ) in the brain and periphery. The biological role of the oxygenated NAEs, such as prostamides, hydroxylated anandamide and DHEA derivatives, are less studied. Evidence is accumulating that NAEs and their oxidative metabolites may be aberrantly regulated or are associated with disease severity in obesity, metabolic syndrome, cancer, neuroinflammation and liver cirrhosis. Here, we comprehensively review NAE biosynthesis and degradation, their metabolism by lipoxygenases, cyclooxygenases and cytochrome P450s and the biological functions of these signaling lipids. We discuss the latest findings and therapeutic potential of modulating endogenous NAE levels by inhibition of their degradation, which is currently under clinical evaluation for neuropsychiatric disorders. We also highlight NAE biosynthesis inhibition as an emerging topic with therapeutic opportunities in endocannabinoid and NAE signaling.
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Affiliation(s)
- Elliot D Mock
- Department of Molecular Physiology, Leiden Institute of Chemistry, Leiden University and Oncode Institute, Einsteinweg 55, Leiden 2333 CC, The Netherlands
| | - Berend Gagestein
- Department of Molecular Physiology, Leiden Institute of Chemistry, Leiden University and Oncode Institute, Einsteinweg 55, Leiden 2333 CC, The Netherlands
| | - Mario van der Stelt
- Department of Molecular Physiology, Leiden Institute of Chemistry, Leiden University and Oncode Institute, Einsteinweg 55, Leiden 2333 CC, The Netherlands.
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Murthy VD, McLarty E, Woolard KD, Parker RL, Kortz G, King JN, Poppenga RH, Knipe MF, Dickinson PJ. Case Report: MRI, Clinical, and Pathological Correlates of Bromethalin Toxicosis in Three Dogs. Front Vet Sci 2022; 9:879007. [PMID: 35558887 PMCID: PMC9087846 DOI: 10.3389/fvets.2022.879007] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/18/2022] [Accepted: 03/16/2022] [Indexed: 11/13/2022] Open
Abstract
Bromethalin toxicosis is an increasingly common clinical presentation in dogs that may be fatal depending on the extent of intoxication. Antemortem diagnosis of bromethalin toxicosis was achieved in three dogs by demonstration of the active metabolite desmethylbromethalin in fat or serum. Magnetic resonance imaging (MRI) findings were consistent with a diffuse leukoencephalopathy with restricted diffusion and prominent involvement of the corticospinal motor tracts on T2-weighted and diffusion-weighted sequences. Imaging findings were confirmed in one non-surviving dog at necropsy. Resolution of MRI abnormalities was demonstrated in one surviving dog that was consistent with the associated resolution of clinical signs. Initial findings in these dogs support further investigation of specific MRI patterns in cases of leukoencephalopathy to aid differential diagnosis. While antemortem detection of bromethalin and its metabolites confirms exposure, quantitation may be informative as a prognostic biomarker.
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Affiliation(s)
- Vishal D. Murthy
- Department of Veterinary Clinical Sciences, College of Veterinary Medicine, Washington State University, Pullman, WA, United States
| | - Ehren McLarty
- Department of Surgical and Radiological Sciences, University of California, Davis, Davis, CA, United States
| | - Kevin D. Woolard
- Department of Pathology, Microbiology and Immunology, University of California, Davis, Davis, CA, United States
| | - Rell L. Parker
- Department of Small Animal Clinical Sciences, Virginia-Maryland Regional College of Veterinary Medicine, Virginia Polytechnic Institute and State University, Blacksburg, VA, United States
| | - Gregg Kortz
- Department of Neurology, VCA Sacramento Veterinary Referral Center, Sacramento, CA, United States
| | - Jamie N. King
- Department of Neurology, VCA Sacramento Veterinary Referral Center, Sacramento, CA, United States
| | - Robert H. Poppenga
- California Animal Health and Food Safety Laboratory System, University of California, Davis, Davis, CA, United States
| | - Marguerite F. Knipe
- Department of Surgical and Radiological Sciences, University of California, Davis, Davis, CA, United States
| | - Peter J. Dickinson
- Department of Surgical and Radiological Sciences, University of California, Davis, Davis, CA, United States
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7
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Proteomic Analysis of Hypoxia-Induced Senescence of Human Bone Marrow Mesenchymal Stem Cells. Stem Cells Int 2021; 2021:5555590. [PMID: 34484348 PMCID: PMC8416403 DOI: 10.1155/2021/5555590] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/25/2021] [Revised: 06/29/2021] [Accepted: 07/28/2021] [Indexed: 12/18/2022] Open
Abstract
Methods Hypoxia in hBMSCs was induced for 0, 4, and 12 hours, and cellular senescence was evaluated by senescence-associated β-galactosidase (SA-β-gal) staining. Tandem mass tag (TMT) labeling was combined with liquid chromatography-tandem mass spectrometry (LC-MS/MS) for differential proteomic analysis of hypoxia in hBMSCs. Parallel reaction monitoring (PRM) analysis was used to validate the candidate proteins. Verifications of signaling pathways were evaluated by western blotting. Cell apoptosis was evaluated using Annexin V/7-AAD staining by flow cytometry. The production of reactive oxygen species (ROS) was detected by the fluorescent probe 2,7-dichlorodihydrofluorescein diacetate (DCFH-DA). Results Cell senescence detected by SA-β-gal activity was higher in the 12-hour hypoxia-induced group. TMT analysis of 12-hour hypoxia-induced cells identified over 6000 proteins, including 686 differentially expressed proteins. Based on biological pathway analysis, we found that the senescence-associated proteins were predominantly enriched in the cancer pathways, PI3K-Akt pathway, and cellular senescence signaling pathways. CDK1, CDK2, and CCND1 were important nodes in PPI analyses. Moreover, the CCND1, UQCRH, and COX7C expressions were verified by PRM. Hypoxia induction for 12 hours in hBMSCs reduced CCND1 expression but promoted ROS production and cell apoptosis. Such effects were markedly reduced by the PI3K agonist, 740 Y-P, and attenuated by LY294002. Conclusions Hypoxia of hBMSCs inhibited CCND1 expression but promoted ROS production and cell apoptosis through activating the PI3K-dependent signaling pathway. These findings provided a detailed characterization of the proteomic profiles related to hypoxia-induced senescence of hBMSCs and facilitated our understanding of the molecular mechanisms leading to stem cell senescence.
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Quitt PR, Brühschwein A, Matiasek K, Wielaender F, Karkamo V, Hytönen MK, Meyer-Lindenberg A, Dengler B, Leeb T, Lohi H, Fischer A. A hypomyelinating leukodystrophy in German Shepherd dogs. J Vet Intern Med 2021; 35:1455-1465. [PMID: 33734486 PMCID: PMC8163122 DOI: 10.1111/jvim.16085] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/30/2020] [Revised: 02/07/2021] [Accepted: 02/17/2021] [Indexed: 12/28/2022] Open
Abstract
BACKGROUND Shaking puppy syndrome is commonly attributed to abnormal myelination of the central nervous system. HYPOTHESIS/OBJECTIVES To report the long-term clinical course and the imaging characteristics of hypomyelinating leukodystrophy in German Shepherd dogs. ANIMALS AND METHODS Three related litters with 11 affected dogs. RESULTS The 11 affected dogs experienced coarse, side-to-side tremors of the head and trunk, which interfered with normal goal-oriented movements and disappeared at rest. Signs were noticed shortly after birth. Nine dogs were euthanized, 3 dogs underwent pathological examination, and 2 littermates were raised by their breeder. Tremors improved gradually until 6 to 7 months of age. Adult dogs walked with severe residual pelvic limb ataxia. One dog developed epilepsy with tonic-clonic seizures at 15 months of age. Conventional magnetic resonance imaging (MRI) disclosed homogenous hyperintense signal of the entire subcortical white matter in 3 affected 7-week-old dogs and a hypointense signal in a presumably unaffected littermate. Subcortical white matter appeared isointense to gray matter at 15 and 27 weeks of age on repeated MRI. Abnormal white matter signal with failure to display normal gray-white matter contrast persisted into adulthood. Cerebellar arbor vitae was not visible at any time point. Clinical signs, MRI findings, and pathological examinations were indicative of a hypomyelinating leukodystrophy. All parents of the affected litters shared a common ancestor and relatedness of the puppies suggested an autosomal recessive mode of inheritance. CONCLUSION We describe a novel hypomyelinating leukodystrophy in German Shepherd dogs with a suspected inherited origin.
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Affiliation(s)
- Pia R Quitt
- Centre for Clinical Veterinary Medicine, Faculty of Veterinary Medicine, LMU Munich, Munich, Germany
| | - Andreas Brühschwein
- Centre for Clinical Veterinary Medicine, Faculty of Veterinary Medicine, LMU Munich, Munich, Germany
| | - Kaspar Matiasek
- Section of Clinical and Comparative Pathology, Faculty of Veterinary Medicine, LMU Munich, Munich, Germany
| | - Franziska Wielaender
- Centre for Clinical Veterinary Medicine, Faculty of Veterinary Medicine, LMU Munich, Munich, Germany
| | - Veera Karkamo
- Production and Companion Animal Pathology Section, Finnish Food Authority, Helsinki, Finland
| | - Marjo K Hytönen
- Department of Medical and Clinical Genetics, University of Helsinki, Helsinki, Finland.,Department of Veterinary Biosciences, University of Helsinki, Helsinki, Finland.,Folkhälsan Research Center, Helsinki, Finland
| | - Andrea Meyer-Lindenberg
- Centre for Clinical Veterinary Medicine, Faculty of Veterinary Medicine, LMU Munich, Munich, Germany
| | - Berett Dengler
- Centre for Clinical Veterinary Medicine, Faculty of Veterinary Medicine, LMU Munich, Munich, Germany
| | - Tosso Leeb
- Institute of Genetics, Vetsuisse Faculty, University of Bern, Bern, Switzerland
| | - Hannes Lohi
- Department of Medical and Clinical Genetics, University of Helsinki, Helsinki, Finland.,Department of Veterinary Biosciences, University of Helsinki, Helsinki, Finland.,Folkhälsan Research Center, Helsinki, Finland
| | - Andrea Fischer
- Centre for Clinical Veterinary Medicine, Faculty of Veterinary Medicine, LMU Munich, Munich, Germany
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Letko A, Minor KM, Friedenberg SG, Shelton GD, Salvador JP, Mandigers PJJ, Leegwater PAJ, Winkler PA, Petersen-Jones SM, Stanley BJ, Ekenstedt KJ, Johnson GS, Hansen L, Jagannathan V, Mickelson JR, Drögemüller C. A CNTNAP1 Missense Variant Is Associated with Canine Laryngeal Paralysis and Polyneuropathy. Genes (Basel) 2020; 11:E1426. [PMID: 33261176 PMCID: PMC7761076 DOI: 10.3390/genes11121426] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/28/2020] [Revised: 11/25/2020] [Accepted: 11/26/2020] [Indexed: 02/06/2023] Open
Abstract
Laryngeal paralysis associated with a generalized polyneuropathy (LPPN) most commonly exists in geriatric dogs from a variety of large and giant breeds. The purpose of this study was to discover the underlying genetic and molecular mechanisms in a younger-onset form of this neurodegenerative disease seen in two closely related giant dog breeds, the Leonberger and Saint Bernard. Neuropathology of an affected dog from each breed showed variable nerve fiber loss and scattered inappropriately thin myelinated fibers. Using across-breed genome-wide association, haplotype analysis, and whole-genome sequencing, we identified a missense variant in the CNTNAP1 gene (c.2810G>A; p.Gly937Glu) in which homozygotes in both studied breeds are affected. CNTNAP1 encodes a contactin-associated protein important for organization of myelinated axons. The herein described likely pathogenic CNTNAP1 variant occurs in unrelated breeds at variable frequencies. Individual homozygous mutant LPPN-affected Labrador retrievers that were on average four years younger than dogs affected by geriatric onset laryngeal paralysis polyneuropathy could be explained by this variant. Pathologic changes in a Labrador retriever nerve biopsy from a homozygous mutant dog were similar to those of the Leonberger and Saint Bernard. The impact of this variant on health in English bulldogs and Irish terriers, two breeds with higher CNTNAP1 variant allele frequencies, remains unclear. Pathogenic variants in CNTNAP1 have previously been reported in human patients with lethal congenital contracture syndrome and hypomyelinating neuropathy, including vocal cord palsy and severe respiratory distress. This is the first report of contactin-associated LPPN in dogs characterized by a deleterious variant that most likely predates modern breed establishment.
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Affiliation(s)
- Anna Letko
- Institute of Genetics, Vetsuisse Faculty, University of Bern, 3012 Bern, Switzerland; (V.J.); (C.D.)
| | - Katie M. Minor
- Department of Veterinary and Biomedical Sciences, College of Veterinary Medicine, University of Minnesota, Saint Paul, MN 55108, USA; (K.M.M.); (J.R.M.)
| | - Steven G. Friedenberg
- Department of Veterinary Clinical Sciences, College of Veterinary Medicine, University of Minnesota, Saint Paul, MN 55108, USA;
| | - G. Diane Shelton
- Department of Pathology, School of Medicine, University of California San Diego, La Jolla, CA 92093-0709, USA; (G.D.S.); (J.P.S.)
| | - Jill Pesayco Salvador
- Department of Pathology, School of Medicine, University of California San Diego, La Jolla, CA 92093-0709, USA; (G.D.S.); (J.P.S.)
| | - Paul J. J. Mandigers
- Department of Clinical Sciences, Utrecht University, 3584 CM Utrecht, The Netherlands; (P.J.J.M.); (P.A.J.L.)
| | - Peter A. J. Leegwater
- Department of Clinical Sciences, Utrecht University, 3584 CM Utrecht, The Netherlands; (P.J.J.M.); (P.A.J.L.)
| | - Paige A. Winkler
- Department of Small Animal Clinical Sciences, College of Veterinary Medicine, Michigan State University, East Lansing, MI 48824, USA; (P.A.W.); (S.M.P.-J.); (B.J.S.)
| | - Simon M. Petersen-Jones
- Department of Small Animal Clinical Sciences, College of Veterinary Medicine, Michigan State University, East Lansing, MI 48824, USA; (P.A.W.); (S.M.P.-J.); (B.J.S.)
| | - Bryden J. Stanley
- Department of Small Animal Clinical Sciences, College of Veterinary Medicine, Michigan State University, East Lansing, MI 48824, USA; (P.A.W.); (S.M.P.-J.); (B.J.S.)
| | - Kari J. Ekenstedt
- Department of Basic Medical Sciences, College of Veterinary Medicine, Purdue University, West Lafayette, IN 47907, USA;
| | - Gary S. Johnson
- Department of Veterinary Pathobiology, University of Missouri, Columbia, MO 65211, USA; (G.S.J.); (L.H.)
| | - Liz Hansen
- Department of Veterinary Pathobiology, University of Missouri, Columbia, MO 65211, USA; (G.S.J.); (L.H.)
| | - Vidhya Jagannathan
- Institute of Genetics, Vetsuisse Faculty, University of Bern, 3012 Bern, Switzerland; (V.J.); (C.D.)
| | - James R. Mickelson
- Department of Veterinary and Biomedical Sciences, College of Veterinary Medicine, University of Minnesota, Saint Paul, MN 55108, USA; (K.M.M.); (J.R.M.)
| | - Cord Drögemüller
- Institute of Genetics, Vetsuisse Faculty, University of Bern, 3012 Bern, Switzerland; (V.J.); (C.D.)
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10
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Letko A, Minor KM, Jagannathan V, Seefried FR, Mickelson JR, Oliehoek P, Drögemüller C. Genomic diversity and population structure of the Leonberger dog breed. Genet Sel Evol 2020; 52:61. [PMID: 33054768 PMCID: PMC7557023 DOI: 10.1186/s12711-020-00581-3] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/18/2020] [Accepted: 10/02/2020] [Indexed: 12/20/2022] Open
Abstract
BACKGROUND Leonberger is a giant dog breed formed in the 1850s in Germany. Its post-World War II popularity has resulted in a current global population of ~ 30,000 dogs. The breed has predispositions to neurodegenerative disorders and cancer, which is likely due in large part to limited genetic diversity. However, to date there is no scientific literature on the overall demography and genomic architecture of this breed. RESULTS We assessed extensive pedigree records, SNP array genotype data, and whole-genome sequences (WGS) on 142,072, 1203 and 39 Leonberger dogs, respectively. Pedigree analyses identified 22 founder animals and revealed an apparent popular sire effect. The average pedigree-based inbreeding coefficient of 0.29 and average kinship of 0.31 show a dramatic loss of genetic diversity. The observed average life span decreased over time from 9.4 years in 1989 to 7.7 years in 2004. A global health survey confirmed a high prevalence of cancer and neurological disorders. Analysis of SNP-based runs of homozygosity (ROH) identified 125,653 ROH with an average length of 5.88 Mb, and confirmed an average inbreeding coefficient of 0.28. Genome-wide filtering of the WGS data revealed 28 non-protein-changing variants that were present in all Leonberger individuals and a list of 22 potentially pathogenic variants for neurological disorders of which 50% occurred only in Leonbergers and 50% occurred rarely in other breeds. Furthermore, one of the two mtDNA haplogroups detected was present in one dog only. CONCLUSIONS The increasing size of the Leonberger population has been accompanied by a considerable loss of genetic diversity after the bottleneck that occurred in the 1940s due to the intensive use of popular sires resulting in high levels of inbreeding. This might explain the high prevalence of certain disorders; however, genomic data provide no evidence for fixed coding variants that explain these predispositions. The list of candidate causative variants for polyneuropathy needs to be further evaluated. Preserving the current genetic diversity is possible by increasing the number of individuals for breeding while restricting the number of litters per sire/dam. In addition, outcrossing would help optimize long-term genetic diversity and contribute to the sustainability and health of the population.
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Affiliation(s)
- Anna Letko
- Institute of Genetics, Vetsuisse Faculty, University of Bern, 3012 Bern, Switzerland
| | - Katie M. Minor
- Department of Veterinary and Biomedical Sciences, College of Veterinary Medicine, University of Minnesota, St. Paul, Minnesota 55108 USA
| | - Vidhya Jagannathan
- Institute of Genetics, Vetsuisse Faculty, University of Bern, 3012 Bern, Switzerland
| | | | - James R. Mickelson
- Department of Veterinary and Biomedical Sciences, College of Veterinary Medicine, University of Minnesota, St. Paul, Minnesota 55108 USA
| | | | - Cord Drögemüller
- Institute of Genetics, Vetsuisse Faculty, University of Bern, 3012 Bern, Switzerland
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11
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Vernau KM, Struys E, Letko A, Woolard KD, Aguilar M, Brown EA, Cissell DD, Dickinson PJ, Shelton GD, Broome MR, Gibson KM, Pearl PL, König F, Van Winkle TJ, O’Brien D, Roos B, Matiasek K, Jagannathan V, Drögemüller C, Mansour TA, Brown CT, Bannasch DL. A Missense Variant in ALDH5A1 Associated with Canine Succinic Semialdehyde Dehydrogenase Deficiency (SSADHD) in the Saluki Dog. Genes (Basel) 2020; 11:genes11091033. [PMID: 32887425 PMCID: PMC7565783 DOI: 10.3390/genes11091033] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/07/2020] [Revised: 08/25/2020] [Accepted: 08/27/2020] [Indexed: 02/07/2023] Open
Abstract
Dogs provide highly valuable models of human disease due to the similarity in phenotype presentation and the ease of genetic analysis. Seven Saluki puppies were investigated for neurological abnormalities including seizures and altered behavior. Magnetic resonance imaging showed a diffuse, marked reduction in cerebral cortical thickness, and symmetrical T2 hyperintensity in specific brain regions. Cerebral cortical atrophy with vacuolation (status spongiosus) was noted on necropsy. Genome-wide association study of 7 affected and 28 normal Salukis revealed a genome-wide significantly associated region on CFA 35. Whole-genome sequencing of three confirmed cases from three different litters revealed a homozygous missense variant within the aldehyde dehydrogenase 5 family member A1 (ALDH5A1) gene (XM_014110599.2: c.866G>A; XP_013966074.2: p.(Gly288Asp). ALDH5A1 encodes a succinic semialdehyde dehydrogenase (SSADH) enzyme critical in the gamma-aminobutyric acid neurotransmitter (GABA) metabolic pathway. Metabolic screening of affected dogs showed markedly elevated gamma-hydroxybutyric acid in serum, cerebrospinal fluid (CSF) and brain, and elevated succinate semialdehyde in urine, CSF and brain. SSADH activity in the brain of affected dogs was low. Affected Saluki dogs had striking similarities to SSADH deficiency in humans although hydroxybutyric aciduria was absent in affected dogs. ALDH5A1-related SSADH deficiency in Salukis provides a unique translational large animal model for the development of novel therapeutic strategies.
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Affiliation(s)
- Karen M. Vernau
- Department of Surgical and Radiological Sciences, University of California Davis, Davis, CA 95616, USA; (D.D.C.); (P.J.D.)
- Correspondence: (K.M.V.); (D.L.B.)
| | - Eduard Struys
- Department of Clinical Chemistry, VU University Medical Center, 1081 HV Amsterdam, The Netherlands; (E.S.); (B.R.)
| | - Anna Letko
- Institute of Genetics, Vetsuisse Faculty, University of Bern, 3001 Bern, Switzerland; (A.L.); (V.J.); (C.D.)
| | - Kevin D. Woolard
- Department of Pathology, Microbiology and Immunology, University of California Davis, Davis, CA 95616, USA;
| | - Miriam Aguilar
- Department of Population Health and Reproduction, University of California Davis, Davis, CA 95616, USA; (M.A.); (E.A.B.); (T.A.M.); (C.T.B.)
| | - Emily A. Brown
- Department of Population Health and Reproduction, University of California Davis, Davis, CA 95616, USA; (M.A.); (E.A.B.); (T.A.M.); (C.T.B.)
| | - Derek D. Cissell
- Department of Surgical and Radiological Sciences, University of California Davis, Davis, CA 95616, USA; (D.D.C.); (P.J.D.)
| | - Peter J. Dickinson
- Department of Surgical and Radiological Sciences, University of California Davis, Davis, CA 95616, USA; (D.D.C.); (P.J.D.)
| | - G. Diane Shelton
- Department of Pathology, University of California San Diego, La Jolla, CA 92093, USA;
| | | | - K. Michael Gibson
- College of Pharmacy and Pharmaceutical Sciences, Washington State University, Spokane, WA 99202, USA;
| | | | - Florian König
- Fachtierarzt fur Kleintiere, Am Berggewann 13, 65199 Wiesbaden, Germany;
| | - Thomas J. Van Winkle
- Department of Pathobiology, School of Veterinary Medicine, University of Pennsylvania, Philadelphia, PA 19104, USA;
| | - Dennis O’Brien
- College of Veterinary Medicine, University of Missouri, Columbia, MO 65211, USA;
| | - B. Roos
- Department of Clinical Chemistry, VU University Medical Center, 1081 HV Amsterdam, The Netherlands; (E.S.); (B.R.)
| | - Kaspar Matiasek
- Clinical and Comparative Neuropathology, Ludwig-Maximilians-Universitaet München, 80539 Munchen, Germany;
| | - Vidhya Jagannathan
- Institute of Genetics, Vetsuisse Faculty, University of Bern, 3001 Bern, Switzerland; (A.L.); (V.J.); (C.D.)
| | - Cord Drögemüller
- Institute of Genetics, Vetsuisse Faculty, University of Bern, 3001 Bern, Switzerland; (A.L.); (V.J.); (C.D.)
| | - Tamer A. Mansour
- Department of Population Health and Reproduction, University of California Davis, Davis, CA 95616, USA; (M.A.); (E.A.B.); (T.A.M.); (C.T.B.)
- Department of Clinical Pathology, School of Medicine, Mansoura University, Mansoura 35516, Egypt
| | - C. Titus Brown
- Department of Population Health and Reproduction, University of California Davis, Davis, CA 95616, USA; (M.A.); (E.A.B.); (T.A.M.); (C.T.B.)
| | - Danika L. Bannasch
- Department of Population Health and Reproduction, University of California Davis, Davis, CA 95616, USA; (M.A.); (E.A.B.); (T.A.M.); (C.T.B.)
- Correspondence: (K.M.V.); (D.L.B.)
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Jagannathan V, Drögemüller C, Leeb T. A comprehensive biomedical variant catalogue based on whole genome sequences of 582 dogs and eight wolves. Anim Genet 2019; 50:695-704. [PMID: 31486122 PMCID: PMC6842318 DOI: 10.1111/age.12834] [Citation(s) in RCA: 135] [Impact Index Per Article: 27.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 06/21/2019] [Indexed: 12/16/2022]
Abstract
The domestic dog serves as an excellent model to investigate the genetic basis of disease. More than 400 heritable traits analogous to human diseases have been described in dogs. To further canine medical genetics research, we established the Dog Biomedical Variant Database Consortium (DBVDC) and present a comprehensive list of functionally annotated genome variants that were identified with whole genome sequencing of 582 dogs from 126 breeds and eight wolves. The genomes used in the study have a minimum coverage of 10× and an average coverage of ~24×. In total, we identified 23 133 692 single-nucleotide variants (SNVs) and 10 048 038 short indels, including 93% undescribed variants. On average, each individual dog genome carried ∼4.1 million single-nucleotide and ~1.4 million short-indel variants with respect to the reference genome assembly. About 2% of the variants were located in coding regions of annotated genes and loci. Variant effect classification showed 247 141 SNVs and 99 562 short indels having moderate or high impact on 11 267 protein-coding genes. On average, each genome contained heterozygous loss-of-function variants in 30 potentially embryonic lethal genes and 97 genes associated with developmental disorders. More than 50 inherited disorders and traits have been unravelled using the DBVDC variant catalogue, enabling genetic testing for breeding and diagnostics. This resource of annotated variants and their corresponding genotype frequencies constitutes a highly useful tool for the identification of potential variants causative for rare inherited disorders in dogs.
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Affiliation(s)
- V Jagannathan
- Institute of Genetics, Vetsuisse Faculty, University of Bern, Bern, Switzerland
| | - C Drögemüller
- Institute of Genetics, Vetsuisse Faculty, University of Bern, Bern, Switzerland
| | - T Leeb
- Institute of Genetics, Vetsuisse Faculty, University of Bern, Bern, Switzerland
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TSEN54 missense variant in Standard Schnauzers with leukodystrophy. PLoS Genet 2019; 15:e1008411. [PMID: 31584937 PMCID: PMC6795476 DOI: 10.1371/journal.pgen.1008411] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/17/2019] [Revised: 10/16/2019] [Accepted: 09/10/2019] [Indexed: 12/13/2022] Open
Abstract
We report a hereditary leukodystrophy in Standard Schnauzer puppies. Clinical signs occurred shortly after birth or started at an age of under 4 weeks and included apathy, dysphoric vocalization, hypermetric ataxia, intension tremor, head tilt, circling, proprioceptive deficits, seizures and ventral strabismus consistent with a diffuse intracranial lesion. Magnetic resonance imaging revealed a diffuse white matter disease without mass effect. Macroscopically, the cerebral white matter showed a gelatinous texture in the centrum semiovale. A mild hydrocephalus internus was noted. Histopathologically, a severe multifocal reduction of myelin formation and moderate diffuse edema without inflammation was detected leading to the diagnosis of leukodystrophy. Combined linkage analysis and homozygosity mapping in two related families delineated critical intervals of approximately 29 Mb. The comparison of whole genome sequence data of one affected Standard Schnauzer to 221 control genomes revealed a single private homozygous protein changing variant in the critical intervals, TSEN54:c.371G>A or p.(Gly124Asp). TSEN54 encodes the tRNA splicing endonuclease subunit 54. In humans, several variants in TSEN54 were reported to cause different types of pontocerebellar hypoplasia. The genotypes at the c.371G>A variant were perfectly associated with the leukodystrophy phenotype in 12 affected Standard Schnauzers and almost 1000 control dogs from different breeds. These results suggest that TSEN54:c.371G>A causes the leukodystrophy. The identification of a candidate causative variant enables genetic testing so that the unintentional breeding of affected Standard Schnauzers can be avoided in the future. Our findings extend the known genotype-phenotype correlation for TSEN54 variants. Various hereditary diseases of the cerebral white matter occur in humans and dogs. We describe a new leukodystrophy in Standard Schnauzers. Genetic mapping and whole genome sequence analysis identified a likely candidate causative variant in the TSEN54 gene encoding tRNA splicing endonuclease 54. These results provide new information about the role of TSEN54 in cell metabolism and the development of the central nervous system in the late gestational and early post-natal period. The affected dogs potentially represent a translational large animal model for similar leukoencephalopathies in human medicine. The clinical phenotype in Schnauzers included multifocal central nervous system signs. A holistic pathogenically driven understanding of disease initiation and perpetuation requires a solid analysis of the underlying genetics and characterization of the disease phenotype at the clinical and cellular as well as sub-cellular level. In contrast to the canine phenotype with a predominant manifestation in the cerebrum white matter, other TSEN54 variants in humans have been reported to result in a different pathological phenotype characterized by pontocerebellar hypoplasia. The differences between humans and dogs underscore the need for comparative analysis at the clinical, pathological and molecular level to understand species-specific protein mediated pathways, interactions and outcomes.
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A Missense Mutation in the Vacuolar Protein Sorting 11 ( VPS11) Gene Is Associated with Neuroaxonal Dystrophy in Rottweiler Dogs. G3-GENES GENOMES GENETICS 2018; 8:2773-2780. [PMID: 29945969 PMCID: PMC6071611 DOI: 10.1534/g3.118.200376] [Citation(s) in RCA: 16] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Indexed: 02/05/2023]
Abstract
Canine neuroaxonal dystrophy (NAD) is a recessive, degenerative neurological disease of young adult Rottweiler dogs (Canis lupus familiaris) characterized pathologically by axonal spheroids primarily targeting sensory axon terminals. A genome-wide association study of seven Rottweilers affected with NAD and 42 controls revealed a significantly associated region on canine chromosome 5 (CFA 5). Homozygosity within the associated region narrowed the critical interval to a 4.46 Mb haplotype (CFA5:11.28 Mb – 15.75 Mb; CanFam3.1) that associated with the phenotype. Whole-genome sequencing of two histopathologically confirmed canine NAD cases and 98 dogs unaffected with NAD revealed a homozygous missense mutation within the Vacuolar Protein Sorting 11 (VPS11) gene (g.14777774T > C; p.H835R) that was associated with the phenotype. These findings present the opportunity for an antemortem test for confirming NAD in Rottweilers where the allele frequency was estimated at 2.3%. VPS11 mutations have been associated with a degenerative leukoencephalopathy in humans, and VSP11 should additionally be included as a candidate gene for unexplained cases of human NAD.
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