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Vanhaesebrouck A, Van Poucke M, Stee K, Granger N, Ives E, Van Soens I, Cornelis I, Bossens K, Peelman L, Van Ham L, Bhatti SFM. Generalized myokymia, or neuromyotonia, or both in dogs with or without spinocerebellar ataxia. J Vet Intern Med 2023; 37:2310-2314. [PMID: 37905444 PMCID: PMC10658559 DOI: 10.1111/jvim.16892] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/30/2023] [Accepted: 09/20/2023] [Indexed: 11/02/2023] Open
Abstract
BACKGROUND KCNJ10 and CAPN1 variants cause "spinocerebellar" ataxia in dogs, but their association with generalized myokymia and neuromyotonia remains unclear. OBJECTIVE To investigate the association between KCNJ10 and CAPN1 and myokymia or neuromyotonia, with or without concurrent spinocerebellar ataxia. ANIMALS Thirty-three client-owned dogs with spinocerebellar ataxia, myokymia neuromytonia, or a combination of these signs. METHODS Genetic analysis of a cohort of dogs clinically diagnosed with spinocerebellar ataxia, myokymia or neuromyotonia. KCNJ10 c.627C>G and CAPN1 c.344G>A variants and the coding sequence of KCNA1, KCNA2, KCNA6, KCNJ10 and HINT1 were sequenced using DNA extracted from blood samples. RESULTS Twenty-four Jack Russell terriers, 1 Jack Russell terrier cross, 1 Dachshund and 1 mixed breed with spinocerebellar ataxia were biallelic (homozygous) for the KCNJ10 c.627C>G variant. Twenty-one of those dogs had myokymia, neuromyotonia, or both. One Parson Russell terrier with spinocerebellar ataxia alone was biallelic for the CAPN1 c.344G>A variant. Neither variant was found in 1 Jack Russell terrier with ataxia alone, nor in 3 Jack Russell terriers and 1 Yorkshire terrier with myokymia and neuromyotonia alone. No other causal variants were found in the coding sequence of the investigated candidate genes in these latter 5 dogs. CONCLUSION The KCNJ10 c.627C>G variant, or rarely the CAPN1 c.344G>A variant, was confirmed to be the causal variant of spinocerebellar ataxia. We also report the presence of the KCNJ10 c.627C>G variant in the Dachshund breed. In dogs with myokymia and neuromyotonia alone the reported gene variants were not found. Other genetic or immune-mediated causes should be investigated to explain the clinical signs of these cases.
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Affiliation(s)
| | - Mario Van Poucke
- Department of Veterinary and Biosciences, Faculty of Veterinary SciencesGhent UniversityMerelbekeBelgium
| | - Kimberley Stee
- Small Animal Department, Faculty of Veterinary SciencesGhent UniversityMerelbekeBelgium
| | | | - Edward Ives
- Anderson Moores Veterinary SpecialistsWinchesterUK
| | - Iris Van Soens
- Companion Animal Clinic, Department of Clinical Sciences, Faculty of Veterinary MedicineUniversity of LiègeLiegeBelgium
| | - Ine Cornelis
- Small Animal Department, Faculty of Veterinary SciencesGhent UniversityMerelbekeBelgium
| | | | - Luc Peelman
- Department of Veterinary and Biosciences, Faculty of Veterinary SciencesGhent UniversityMerelbekeBelgium
| | - Luc Van Ham
- Small Animal Department, Faculty of Veterinary SciencesGhent UniversityMerelbekeBelgium
| | - Sofie F. M. Bhatti
- Small Animal Department, Faculty of Veterinary SciencesGhent UniversityMerelbekeBelgium
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Stee K, Van Poucke M, Lowrie M, Van Ham L, Peelman L, Olby N, Bhatti SF. Phenotypic and genetic aspects of hereditary ataxia in dogs. J Vet Intern Med 2023; 37:1306-1322. [PMID: 37341581 PMCID: PMC10365067 DOI: 10.1111/jvim.16742] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/16/2022] [Accepted: 05/07/2023] [Indexed: 06/22/2023] Open
Abstract
Hereditary ataxias are a large group of neurodegenerative diseases that have cerebellar or spinocerebellar dysfunction as core feature, occurring as an isolated sign or as part of a syndrome. Based on neuropathology, this group of diseases has so far been classified into cerebellar cortical degenerations, spinocerebellar degenerations, cerebellar ataxias without substantial neurodegeneration, canine multiple system degeneration, and episodic ataxia. Several new hereditary ataxia syndromes are described, but most of these diseases have similar clinical signs and unspecific diagnostic findings, wherefore achieving a definitive diagnosis in these dogs is challenging. Eighteen new genetic variants associated with these diseases have been discovered in the last decade, allowing clinicians to reach a definitive diagnosis for most of these conditions, and allowing breeding schemes to adapt to prevent breeding of affected puppies. This review summarizes the current knowledge about hereditary ataxias in dogs, and proposes to add a "multifocal degenerations with predominant (spino)cerebellar component" category regrouping canine multiple system degeneration, new hereditary ataxia syndromes that do not fit in 1 of the previous categories, as well as specific neuroaxonal dystrophies and lysosomal storage diseases that cause major (spino)cerebellar dysfunction.
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Affiliation(s)
- Kimberley Stee
- Small Animal DepartmentFaculty of Veterinary Medicine, Ghent UniversityMerelbekeBelgium
| | - Mario Van Poucke
- Department of Veterinary and BiosciencesFaculty of Veterinary Sciences, Ghent UniversityMerelbekeBelgium
| | | | - Luc Van Ham
- Small Animal DepartmentFaculty of Veterinary Medicine, Ghent UniversityMerelbekeBelgium
| | - Luc Peelman
- Department of Veterinary and BiosciencesFaculty of Veterinary Sciences, Ghent UniversityMerelbekeBelgium
| | - Natasha Olby
- Department of Clinical SciencesNorth Carolina State UniversityRaleighNorth CarolinaUSA
| | - Sofie F.M. Bhatti
- Small Animal DepartmentFaculty of Veterinary Medicine, Ghent UniversityMerelbekeBelgium
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Stee K, Van Poucke M, Pumarola M, Geerinckx L, Van Soens I, Bhatti SFM, Peelman L, Cornelis I. Spinocerebellar ataxia in the Bouvier des Ardennes breed is caused by a KCNJ10 missense variant. J Vet Intern Med 2022; 37:216-222. [PMID: 36426918 PMCID: PMC9889618 DOI: 10.1111/jvim.16594] [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: 07/22/2022] [Accepted: 11/17/2022] [Indexed: 11/27/2022] Open
Abstract
BACKGROUND In Belgian Malinois, a KCNJ10 variant causes progressive spinocerebellar degeneration. HYPOTHESIS/OBJECTIVES Describe the clinical, diagnostic, pathological and genetic features of spinocerebellar degeneration in the Bouvier des Ardennes breed. ANIMALS Five affected Bouvier des Ardennes puppies with spinocerebellar ataxia (SCA), 8 healthy related dogs, and 63 healthy unrelated Bouvier des Ardennes. METHODS Sequential case study. RESULTS Clinical signs started at 6 weeks of age in 1 puppy with severe signs of cerebellar disease, and at 7 to 10 weeks of age in the 4 remaining puppies with milder signs of spinocerebellar disease. The first puppy displayed severe intention tremors and rapidly progressive generalized hypermetric ataxia, whereas the 4 others developed a milder progressive SCA. Euthanasia after progression to nonambulatory status was performed by 8 weeks of age in the first puppy, and before 11 months of age in the 4 remaining puppies. Histopathology revealed cerebellar spongy degeneration and a focal symmetrical demyelinating myelopathy. All cases were homozygous for KCNJ10 XM_545752.6:c.986T>C(p.(Leu329Pro)), which is pathogenic for SCA with (or without) myokymia, seizures or both (SAMS) and spongy degeneration and cerebellar ataxia (SDCA) 1 in Belgian Malinois dogs. All sampled parents were heterozygous and none of the healthy dogs were homozygous for this recessive variant. This variant has an allele frequency of 15% in the 63 healthy dogs studied. CONCLUSIONS AND CLINICAL IMPORTANCE Inherited spinocerebellar degeneration also affects the Bouvier des Ardennes breed and is caused by a KCNJ10 variant. It can present with a spectrum of severity grades, ranging from severe cerebellar to milder spinocerebellar signs.
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Affiliation(s)
- Kimberley Stee
- Small Animals Department, Faculty of Veterinary MedicineGhent UniversityMerelbekeBelgium
| | - Mario Van Poucke
- Department of Veterinary and Biosciences, Faculty of Veterinary MedicineGhent UniversityMerelbekeBelgium
| | - Martí Pumarola
- Mouse and Comparative Pathology Unit, Department of Animal Medicine and Surgery, Faculty of Veterinary MedicineUniversitat Autònoma de BarcelonaBellaterra (Barcelona)Spain
| | - Lise Geerinckx
- Department of Pathobiology, Pharmacology and Zoological Medicine, Faculty of Veterinary MedicineUniversity of GhentGhentBelgium
| | - Iris Van Soens
- Department of Companion Animal Clinical Sciences, Faculty of Veterinary MedicineUniversity of LiègeLiègeBelgium
| | - Sofie F. M. Bhatti
- Small Animals Department, Faculty of Veterinary MedicineGhent UniversityMerelbekeBelgium
| | - Luc Peelman
- Department of Veterinary and Biosciences, Faculty of Veterinary MedicineGhent UniversityMerelbekeBelgium
| | - Ine Cornelis
- Small Animals Department, Faculty of Veterinary MedicineGhent UniversityMerelbekeBelgium
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Fisher C, Liebel F. Neuromyotonia, myokymia and spinocerebellar ataxia in two Patterdale terrier littermates. VETERINARY RECORD CASE REPORTS 2022. [DOI: 10.1002/vrc2.439] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
Affiliation(s)
- Chloe Fisher
- Langford Veterinary Services, University of Bristol Bristol UK
| | - Francois Liebel
- Langford Veterinary Services, University of Bristol Bristol UK
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Cerda-Gonzalez S, Packer RA, Garosi L, Lowrie M, Mandigers PJJ, O'Brien DP, Volk HA. International veterinary canine dyskinesia task force ECVN consensus statement: Terminology and classification. J Vet Intern Med 2021; 35:1218-1230. [PMID: 33769611 PMCID: PMC8162615 DOI: 10.1111/jvim.16108] [Citation(s) in RCA: 13] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/09/2021] [Accepted: 03/09/2021] [Indexed: 02/07/2023] Open
Abstract
Movement disorders are a heterogeneous group of clinical syndromes in humans and animals characterized by involuntary movements without changes in consciousness. Canine movement disorders broadly include tremors, peripheral nerve hyperexcitability disorders, paroxysmal dyskinesia, and dystonia. Of these, canine paroxysmal dyskinesias remain one of the more difficult to identify and characterize in dogs. Canine paroxysmal dyskinesias include an array of movement disorders in which there is a recurrent episode of abnormal, involuntary, movement. In this consensus statement, we recommend standard terminology for describing the various movement disorders with an emphasis on paroxysmal dyskinesia, as well as a preliminary classification and clinical approach to reporting cases. In the clinical approach to movement disorders, we recommend categorizing movements into hyperkinetic vs hypokinetic, paroxysmal vs persistent, exercise‐induced vs not related to exercise, using a detailed description of movements using the recommended terminology presented here, differentiating movement disorders vs other differential diagnoses, and then finally, determining whether the paroxysmal dyskinesia is due to either inherited or acquired etiologies. This consensus statement represents a starting point for consistent reporting of clinical descriptions and terminology associated with canine movement disorders, with additional focus on paroxysmal dyskinesia. With consistent reporting and identification of additional genetic mutations responsible for these disorders, our understanding of the phenotype, genotype, and pathophysiology will continue to develop and inform further modification of these recommendations.
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Affiliation(s)
| | - Rebecca A Packer
- Department of Clinical Sciences, College of Veterinary Medicine and Biomedical Sciences, Colorado State University, Fort Collins, Colorado, USA
| | | | - Mark Lowrie
- Dovecote Veterinary Hospital, Derby, United Kingdom
| | - Paul J J Mandigers
- Department of Clinical Sciences, Faculty of Veterinary Medicine, Utrecht University, Utrecht, The Netherlands
| | - Dennis P O'Brien
- Department of Veterinary Medicine and Surgery, College of Veterinary Medicine, University of Missouri, Columbia, Missouri, USA
| | - Holger A Volk
- Department of Small Animal Medicine and Surgery, University of Veterinary Medicine Hannover, Hannover, Germany
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Truncating SLC12A6 variants cause different clinical phenotypes in humans and dogs. Eur J Hum Genet 2019; 27:1561-1568. [PMID: 31160700 DOI: 10.1038/s41431-019-0432-3] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/28/2019] [Revised: 05/06/2019] [Accepted: 05/14/2019] [Indexed: 12/13/2022] Open
Abstract
Clinical, pathological, and genetic findings of a primary hereditary ataxia found in a Malinois dog family are described and compared with its human counterpart. Based on the family history and the phenotype/genotype relationships already described in humans and dogs, a causal variant was expected to be found in KCNJ10. Rather surprisingly, whole-exome sequencing identified the SLC12A6 NC_006612.3(XM_014109414.2): c.178_181delinsCATCTCACTCAT (p.(Met60Hisfs*14)) truncating variant. This loss-of-function variant perfectly segregated within the affected Malinois family in an autosomal recessive way and was not found in 562 additional reference dogs from 18 different breeds, including Malinois. In humans, SLC12A6 variants cause "agenesis of the corpus callosum with peripheral neuropathy" (ACCPN, alias Andermann syndrome), owing to a dysfunction of this K+-Cl- cotransporter. However, depending on the variant (including truncating variants), different clinical features are observed within ACCPN. The variant in dogs encodes the shortest isoform described so far and its resultant phenotype is quite different from humans, as no signs of peripheral neuropathy, agenesis of the corpus callosum nor obvious mental retardation have been observed in dogs. On the other hand, progressive spinocerebellar ataxia, which is the most important feature of the canine phenotype, hindlimb paresis, and myokymia-like muscle contractions have not been described in humans with ACCPN so far. As this is the first report of a naturally occurring disease-causing SLC12A6 variant in a non-human species, the canine model will be highly valuable to better understand the complex molecular pathophysiology of SLC12A6-related neurological disorders and to evaluate novel treatment strategies.
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Zakia LS, Palumbo MIP, Teixeira RBC, Resende LAL, Soares MP, de Oliveira-Filho JP, Amorim RM, Borges AS. Neuromyotonia in a horse. J Vet Intern Med 2018; 33:287-291. [PMID: 30511761 PMCID: PMC6335518 DOI: 10.1111/jvim.15353] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/10/2018] [Accepted: 09/21/2018] [Indexed: 01/04/2023] Open
Abstract
This article describes the clinical and electromyographic findings of neuromyotonia in a 19‐month‐old male crossbred Quarter Horse that presented with stiffness and muscle asymmetry in the hind limbs as well as sacrococcygeal, paravertebral, and gluteal myokymia. An electromyographic study showed spontaneous continuous muscle fiber activity with high‐frequency discharges, fibrillations, positive sharp waves, fasciculation potentials, and complex repetitive discharges. Histological examination of the gluteal muscle showed a mixed neurogenic and myopathic pattern. The findings are consistent with neuromyotonia.
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Affiliation(s)
- Luiza Stachewski Zakia
- Department of Veterinary Clinical Sciences, School of Veterinary Medicine and Animal Sciences, Sao Paulo State University (Unesp), Botucatu, Sao Paulo, Brazil
| | - Mariana Isa Pocci Palumbo
- School of Veterinary Medicine and Animal Sciences, Federal University of Mato Grosso do Sul, Campo Grande, Mato Grosso do Sul, Brazil
| | | | - Luiz Antônio Lima Resende
- Department of Neurology, Psychology and Psychiatry, School of Medicine of Botucatu, Sao Paulo State University (Unesp), Botucatu, Sao Paulo, Brazil
| | | | - José Paes de Oliveira-Filho
- Department of Veterinary Clinical Sciences, School of Veterinary Medicine and Animal Sciences, Sao Paulo State University (Unesp), Botucatu, Sao Paulo, Brazil
| | - Rogério Martins Amorim
- Department of Veterinary Clinical Sciences, School of Veterinary Medicine and Animal Sciences, Sao Paulo State University (Unesp), Botucatu, Sao Paulo, Brazil
| | - Alexandre Secorun Borges
- Department of Veterinary Clinical Sciences, School of Veterinary Medicine and Animal Sciences, Sao Paulo State University (Unesp), Botucatu, Sao Paulo, Brazil
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Van Poucke M, Stee K, Bhatti SFM, Vanhaesebrouck A, Bosseler L, Peelman LJ, Van Ham L. The novel homozygous KCNJ10 c.986T>C (p.(Leu329Pro)) variant is pathogenic for the SeSAME/EAST homologue in Malinois dogs. Eur J Hum Genet 2016; 25:222-226. [PMID: 27966545 DOI: 10.1038/ejhg.2016.157] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/01/2016] [Revised: 09/21/2016] [Accepted: 09/29/2016] [Indexed: 12/31/2022] Open
Abstract
SeSAME/EAST syndrome is a multisystemic disorder in humans, characterised by seizures, sensorineural deafness, ataxia, developmental delay and electrolyte imbalance. It is exclusively caused by homozygous or compound heterozygous variations in the KCNJ10 gene. Here we describe a similar syndrome in two families belonging to the Malinois dog breed, based on clinical, neurological, electrodiagnostic and histopathological examination. Genetic analysis detected a novel pathogenic KCNJ10 c.986T>C (p.(Leu329Pro)) variant that is inherited in an autosomal recessive way. This variant has an allele frequency of 2.9% in the Belgian Malinois population, but is not found in closely related dog breeds or in dog breeds where similar symptoms have been already described. The canine phenotype is remarkably similar to humans, including ataxia and seizures. In addition, in half of the dogs clinical and electrophysiological signs of neuromyotonia were observed. Because there is currently no cure and treatment is nonspecific and unsatisfactory, this canine translational model could be used for further elucidating the genotype/phenotype correlation of this monogenic multisystem disorder and as an excellent intermediate step for drug safety testing and efficacy evaluations before initiating human studies.
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Affiliation(s)
- Mario Van Poucke
- Department of Nutrition, Genetics and Ethology, Faculty of Veterinary Medicine, Ghent University, Merelbeke, Belgium
| | - Kimberley Stee
- Department of Small Animal Medicine and Clinical Biology, Faculty of Veterinary Medicine, Ghent University, Merelbeke, Belgium
| | - Sofie F M Bhatti
- Department of Small Animal Medicine and Clinical Biology, Faculty of Veterinary Medicine, Ghent University, Merelbeke, Belgium
| | - An Vanhaesebrouck
- Department of Clinical Neurosciences, John Radcliffe Hospital, University of Oxford, Oxford, UK
| | - Leslie Bosseler
- Department of Pathology, Bacteriology and Poultry Diseases, Faculty of Veterinary Medicine, Ghent University, Merelbeke, Belgium
| | - Luc J Peelman
- Department of Nutrition, Genetics and Ethology, Faculty of Veterinary Medicine, Ghent University, Merelbeke, Belgium
| | - Luc Van Ham
- Department of Small Animal Medicine and Clinical Biology, Faculty of Veterinary Medicine, Ghent University, Merelbeke, Belgium
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O’Sullivan B, Steele T, Ellul M, Kirby E, Duale A, Kier G, Crooks D, Jacob A, Solomon T, Michael B. When should we test for voltage-gated potassium channel complex antibodies? A retrospective case control study. J Clin Neurosci 2016; 33:198-204. [DOI: 10.1016/j.jocn.2016.04.021] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/24/2016] [Revised: 04/12/2016] [Accepted: 04/20/2016] [Indexed: 12/22/2022]
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Gast AC, Metzger J, Tipold A, Distl O. Genome-wide association study for hereditary ataxia in the Parson Russell Terrier and DNA-testing for ataxia-associated mutations in the Parson and Jack Russell Terrier. BMC Vet Res 2016; 12:225. [PMID: 27724896 PMCID: PMC5057501 DOI: 10.1186/s12917-016-0862-x] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/08/2016] [Accepted: 10/06/2016] [Indexed: 12/18/2022] Open
Abstract
Background Spinocerebellar ataxia also referred to as hereditary ataxia comprises different forms of progressive neurodegenerative diseases. A complex mode of inheritance was most likely in Parson Russell Terriers (PRT) and in Jack Russell Terriers (JRT). Recently, the missense mutation KCNJ10:c.627C > G was shown to be associated with the spinocerebellar ataxia (SCA) in JRT and related Russell group of terriers, whereas the missense mutation CAPN1:c.344G > A was associated with late onset ataxia (LOA) in PRT. Results We performed a genome-wide association study (GWAS) in PRT including 15 cases and 29 controls and found a statistically strong signal in the genomic region on dog chromosome 38 (CFA38) where KCNJ10 is located. We tested the CAPN1:c.344G > A and KCNJ10:c.627C > G (Transcript XM_545752.4) mutations in a sample of 77 PRT and 9 JRT from Germany as well as further 179 controls from 20 different dog breeds. All cases and controls genotyped carried the wild-type for the CAPN1:c.344G > A mutation. Among the PRT, 17/77 (22.1 %) dogs were homozygous for the mutant KCNJ10 allele and 22/77 (28.6 %) dogs were heterozygous. Three cases of PRT had the homozygous KCNJ10 wild-type. In JRT, 1/3 cases did show the mutant KCNJ10 allele homozygous. Thus, we sequenced the KCNJ10 exons with their adjacent regions from 10 PRT and 3 JRT including the animals with imperfect co-segregation of the c.627C > G mutation. We identified a total of 45 genetic variants within KCNJ10. The most likely variant explaining the cases appeared a 1-bp-insertion in a C-stretch within exon 3 (KCNJ10:g.22141027insC). In silico analysis showed that this indel may influence the regulation of gene expression. Conclusions In the present study, 16/21 cases of hereditary ataxia perfectly co-segregated with the KCNJ10:c.627C > G mutation. The CAPN1:c.344G > A mutation could not be validated and seems to be a rare variant in the samples screened. Screening KCNJ10 for further mutations did result in a genetic variant explaining 2 JRT cases but further 3 cases with a non-mutant homozygous c.627C > G genotype could not be resolved. Breeders have to be aware that DNA-testing for hereditary ataxia in PRT and JRT does not capture all cases of hereditary ataxia in these dog breeds. At least one further form of hereditary ataxia not yet resolved by a mutation may occur in PRT and JRT. Electronic supplementary material The online version of this article (doi:10.1186/s12917-016-0862-x) contains supplementary material, which is available to authorized users.
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Affiliation(s)
- Alana Christina Gast
- Institute for Animal Breeding and Genetics, University of Veterinary Medicine Hannover, Bünteweg 17p, 30559, Hannover, Germany
| | - Julia Metzger
- Institute for Animal Breeding and Genetics, University of Veterinary Medicine Hannover, Bünteweg 17p, 30559, Hannover, Germany
| | - Andrea Tipold
- Department of Small Animal Medicine and Surgery, University of Veterinary Medicine Hannover, Bünteweg 9, 30559, Hannover, Germany
| | - Ottmar Distl
- Institute for Animal Breeding and Genetics, University of Veterinary Medicine Hannover, Bünteweg 17p, 30559, Hannover, Germany.
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Lowrie M, Garosi L. Classification of involuntary movements in dogs: Tremors and twitches. Vet J 2016; 214:109-16. [PMID: 27387736 DOI: 10.1016/j.tvjl.2016.05.011] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/25/2016] [Revised: 04/25/2016] [Accepted: 05/17/2016] [Indexed: 10/21/2022]
Abstract
This review focuses on important new findings in the field of involuntary movements (IM) in dogs and illustrates the importance of developing a clear classification tool for diagnosing tremor and twitches. Developments over the last decade have changed our understanding of IM and highlight several caveats in the current tremor classification. Given the ambiguous association between tremor phenomenology and tremor aetiology, a more cautious definition of tremors based on clinical assessment is required. An algorithm for the characterisation of tremors is presented herein. The classification of tremors is based on the distinction between tremors that occur at rest and tremors that are action-related; tremors associated with action are divided into postural or kinetic. Controversial issues are outlined and thus reflect the open questions that are yet to be answered from an evidence base of peer-reviewed published literature. Peripheral nerve hyper-excitability (PNH; cramps and twitches) may manifest as fasciculations, myokymia, neuromyotonia, cramps, tetany and tetanus. It is anticipated that as we learn more about the aetiology and pathogenesis of IMs, future revisions to the classification will be needed. It is therefore the intent of this work to stimulate discussions and thus contribute to the development of IM research.
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Affiliation(s)
- Mark Lowrie
- Dovecote Veterinary Hospital, 5 Delven Lane, Castle Donington, Derby DE74 2LJ, UK.
| | - Laurent Garosi
- Davies Veterinary Specialists, Manor Farm Business Park, Higham Gobion, Hitchin SG5 3HR, UK
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Lowrie M, Garosi L. Natural history of canine paroxysmal movement disorders in Labrador retrievers and Jack Russell terriers. Vet J 2016; 213:33-7. [PMID: 27240912 DOI: 10.1016/j.tvjl.2016.03.007] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/23/2015] [Revised: 02/29/2016] [Accepted: 03/03/2016] [Indexed: 10/22/2022]
Abstract
Delineation of the typical disease progression in canine paroxysmal dyskinesia (PD) may assist in evaluating therapeutic agents during clinical trials. Our objective was to establish the natural disease course in a group of dogs diagnosed with PD that received no medication. Fifty-nine dogs (36 Labradors, 23 JRTs) with clinically confirmed PD and a follow-up of ≥3 years were retrospectively reviewed. Dogs with PD had a young onset, were triggered by startle or sudden movements, and had a male bias (75%) with the majority being entire sample population. Twenty-one dogs (36%) had at least one event comprising cluster episodes. Episode duration and frequency varied dramatically, even within an individual. Median follow-up was 7 years. No concurrent disease was identified in any dog that was investigated. The natural history was self-limiting with 32% entering remission and an improvement in 75%. Episodes reduced in terms of frequency and duration in Labradors and JRTs respectively. Remission was lower in dogs with cluster episodes than those without. These findings suggest that the diagnostic yield of advanced neuroimaging techniques in dogs with video footage and historical data supporting PD, without neurological deficits, is low. The presence of cluster episodes is of predictive value for the prognosis of canine PD. Future research should be cautious in reporting treatment response for PD without first considering the spontaneous remission rate and improvements in untreated dogs documented in this study.
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Affiliation(s)
- Mark Lowrie
- Dovecote Veterinary Hospital, 5 Delven Lane, Castle Donington, Derby DE74 2LJ, UK.
| | - Laurent Garosi
- Davies Veterinary Specialists, Manor Farm Business Park, Higham Gobion, Hitchin SG5 3HR, UK
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13
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Rogatko CP, Glass EN, Kent M, Hammond JJ, de Lahunta A. Use of botulinum toxin type A for the treatment of radiation therapy-induced myokymia and neuromyotonia in a dog. J Am Vet Med Assoc 2016; 248:532-7. [PMID: 26885596 DOI: 10.2460/javma.248.5.532] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022]
Abstract
CASE DESCRIPTION A 5-year-old castrated male Maltese was evaluated for intermittent clinical signs of muscle cramping and abnormal movements of the skin of the right pelvic limb at the site where an infiltrative lipoma had twice been resected. After the second surgery, the surgical field was treated with radiation therapy (RT). The clinical signs developed approximately 14 months after completion of RT. CLINICAL FINDINGS When clinical signs were present, the right biceps femoris and semitendinosus muscles in the area that received RT were firm and had frequently visible contractions, and the skin overlying those muscles had episodic vermiform movements. Electromyography of those muscles revealed abnormal spontaneous activity with characteristics consistent with myokymic discharges and neuromyotonia. Magnetic resonance imaging of the affected leg revealed no evidence of tumor regrowth. The myokymia and neuromyotonia were considered secondary to RT. TREATMENT AND OUTCOME 4 U of Clostridium botulinum toxin type A (BoNT-A) neurotoxin complex was injected into the affected muscles at each of 6 sites twice during a 24-hour period (ie, 48 U of BoNT-A were administered). The clinical signs were completely resolved 10 days after BoNT-A treatment and were controlled by repeated BoNT-A treatment every 3 to 4 months for > 1 year. CLINICAL RELEVANCE To our knowledge, this is the first report of myokymia and neuromyotonia secondary to RT in a dog. For the dog of this report, injection of BoNT-A into the affected muscles was safe, effective, and easy to perform.
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A KCNJ10 mutation previously identified in the Russell group of terriers also occurs in Smooth-Haired Fox Terriers with hereditary ataxia and in related breeds. Acta Vet Scand 2015; 57:26. [PMID: 25998802 PMCID: PMC4445810 DOI: 10.1186/s13028-015-0115-1] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/10/2015] [Accepted: 05/15/2015] [Indexed: 11/23/2022] Open
Abstract
Background Hereditary ataxias with similar phenotypes were reported in the Smooth-Haired Fox Terrier, the Jack Russell Terrier and the Parson Russell Terrier. However, segregation analyses showed differing inheritance modes in these breeds. Recently, molecular genetic studies on the Russell group of terriers found independent mutations in KCNJ10 and CAPN1, each associated with a specific clinical subtype of inherited ataxia. The aim of this study was to clarify whether or not Smooth-Haired Fox Terriers with hereditary ataxia and dogs of other related breeds harbor either of the same mutations. A sub goal was to update the results of KCNJ10 genotyping in Russell group terriers. Findings Three Smooth-Haired Fox Terriers with hereditary ataxia and two Toy Fox Terriers with a similar phenotype were all homozygous for the KCNJ10 mutation. The same mutation was also found in a heterozygous state in clinically unaffected Tenterfield Terriers (n = 5) and, in agreement with previous studies, in Jack Russell Terriers, Parson Russell Terriers, and Russell Terriers. Conclusions A KCNJ10 mutation, previously associated with an autosomal recessive spinocerebellar ataxia in Jack Russell Terriers, Parson Russell Terriers, and Russell Terriers segregates in at least three more breeds descended from British hunting terriers. Ataxic members of two of these breeds, the Smooth-Haired Fox Terrier and the Toy Fox Terrier, were homozygous for the mutation, strengthening the likelihood that this genetic defect is indeed the causative mutation for the disease known as “hereditary ataxia” in Fox Terriers and “spinocerebellar ataxia with myokymia, seizures or both” in the Russell group of terriers.
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15
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Abstract
Paroxysmal dyskinesias are episodic movement disorders characterized by muscle hypertonicity that can produce involuntary movements. Signs emanate from the central nervous system; consciousness is not impaired, ictal electroencephalography is normal, and there are no autonomic signs, distinguishing them from seizure disorders. In humans they are classified into 3 groups, each responding to different therapies. A mutation in the gene for brevican (BCAN) has been identified as the cause of Episodic Falling in Cavalier King Charles spaniels. Further elucidation of the genetic causes will enhance our ability to identify and treat these canine diseases.
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Affiliation(s)
- Ganokon Urkasemsin
- Department of Pre-Clinic and Applied Animal Science, Faculty of Veterinary Science, Mahidol University, 999 Phuttamonthon Sai 4 Road, Salaya, Phuttamonthon, Nakhon Pathom 73170, Thailand
| | - Natasha J Olby
- Department of Clinical Sciences, College of Veterinary Medicine, North Carolina State University, 1060 William Moore Drive, Raleigh, NC 27607, USA.
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16
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Abstract
The hereditary ataxias are a group of neurodegenerative diseases that cause a progressive (or episodic) cerebellar ataxia. A large number of different disorders have been described in different breeds of purebred dog, and in some instances, more than one disorder occurs in a single breed, creating a confusing clinical picture. The mutations associated with these disorders are being described at a rapid rate, potentially changing our ability to prevent, diagnose, and treat affected dogs. A breed-related neurodegenerative process should be suspected in any pure bred dog with slowly progressive, symmetric signs of ataxia.
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Affiliation(s)
- Ganokon Urkasemsin
- Department of Pre-Clinic and Applied Animal Science, Faculty of Veterinary Science, Mahidol University, 999 Phuttamonthon Sai 4 Road, Salaya, Phuttamonthon, Nakhon Pathom 73170, Thailand
| | - Natasha J Olby
- Department of Clinical Sciences, College of Veterinary Medicine, North Carolina State University, 1060 William Moore Drive, Raleigh, NC 27607, USA.
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17
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Carvalho FKL, Nascimento EM, Rocha BP, Mendonça FS, Veschi JLA, Silva SMMS, Medeiros RMT, Riet-Correa F. Hybanthus calceolaria poisoning in cattle. J Vet Diagn Invest 2014; 26:674-7. [PMID: 25085870 DOI: 10.1177/1040638714544685] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/17/2022] Open
Abstract
Hybanthus calceolaria, also known as "papaconha" or "ipepacuanha," is a herbaceous plant found in northeastern Brazil, which is often implicated by farmers as the cause of neurological signs in livestock grazing. Several poisoning outbreaks associated with the ingestion of this plant were observed in cattle in the municipalities of Colônia de Gurguéia in the state of Piauí and Sirinhaém in the state of Pernambuco, Brazil. The main clinical signs were ataxia, recumbency, and myokymia. No significant lesions were observed during necropsy or on histological examination. The disease was experimentally reproduced by the administration of 2 daily doses of 40 g/kg/body weight of the fresh green plant containing fruits. The plants without fruits were nontoxic, which is in accordance with the farmers' information, as it was stated that the poisoning only occurs when the plant is fruiting.
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Affiliation(s)
- Fabricio K L Carvalho
- Federal University of Campina Grande, Hospital Veterinario, Patos, Paraíba, Brazil (Carvalho, Nascimento, Medeiros, Riet-Correa)Federal University of Pernambuco, Recife, Pernambuco, Brazil (Rocha, Mendonça)Federal University of Piauí, Piauí, Brazil (Silva)Embrapa Semiárido, Centro de Pesquisa Agropecuaria do Tropico Semi-Árido, Brasilia, Federal District, Brazil (Veschi)
| | - Eduardo M Nascimento
- Federal University of Campina Grande, Hospital Veterinario, Patos, Paraíba, Brazil (Carvalho, Nascimento, Medeiros, Riet-Correa)Federal University of Pernambuco, Recife, Pernambuco, Brazil (Rocha, Mendonça)Federal University of Piauí, Piauí, Brazil (Silva)Embrapa Semiárido, Centro de Pesquisa Agropecuaria do Tropico Semi-Árido, Brasilia, Federal District, Brazil (Veschi)
| | - Brena P Rocha
- Federal University of Campina Grande, Hospital Veterinario, Patos, Paraíba, Brazil (Carvalho, Nascimento, Medeiros, Riet-Correa)Federal University of Pernambuco, Recife, Pernambuco, Brazil (Rocha, Mendonça)Federal University of Piauí, Piauí, Brazil (Silva)Embrapa Semiárido, Centro de Pesquisa Agropecuaria do Tropico Semi-Árido, Brasilia, Federal District, Brazil (Veschi)
| | - Fábio S Mendonça
- Federal University of Campina Grande, Hospital Veterinario, Patos, Paraíba, Brazil (Carvalho, Nascimento, Medeiros, Riet-Correa)Federal University of Pernambuco, Recife, Pernambuco, Brazil (Rocha, Mendonça)Federal University of Piauí, Piauí, Brazil (Silva)Embrapa Semiárido, Centro de Pesquisa Agropecuaria do Tropico Semi-Árido, Brasilia, Federal District, Brazil (Veschi)
| | - Josir L A Veschi
- Federal University of Campina Grande, Hospital Veterinario, Patos, Paraíba, Brazil (Carvalho, Nascimento, Medeiros, Riet-Correa)Federal University of Pernambuco, Recife, Pernambuco, Brazil (Rocha, Mendonça)Federal University of Piauí, Piauí, Brazil (Silva)Embrapa Semiárido, Centro de Pesquisa Agropecuaria do Tropico Semi-Árido, Brasilia, Federal District, Brazil (Veschi)
| | - Silvana M M S Silva
- Federal University of Campina Grande, Hospital Veterinario, Patos, Paraíba, Brazil (Carvalho, Nascimento, Medeiros, Riet-Correa)Federal University of Pernambuco, Recife, Pernambuco, Brazil (Rocha, Mendonça)Federal University of Piauí, Piauí, Brazil (Silva)Embrapa Semiárido, Centro de Pesquisa Agropecuaria do Tropico Semi-Árido, Brasilia, Federal District, Brazil (Veschi)
| | - Rosane M T Medeiros
- Federal University of Campina Grande, Hospital Veterinario, Patos, Paraíba, Brazil (Carvalho, Nascimento, Medeiros, Riet-Correa)Federal University of Pernambuco, Recife, Pernambuco, Brazil (Rocha, Mendonça)Federal University of Piauí, Piauí, Brazil (Silva)Embrapa Semiárido, Centro de Pesquisa Agropecuaria do Tropico Semi-Árido, Brasilia, Federal District, Brazil (Veschi)
| | - Franklin Riet-Correa
- Federal University of Campina Grande, Hospital Veterinario, Patos, Paraíba, Brazil (Carvalho, Nascimento, Medeiros, Riet-Correa)Federal University of Pernambuco, Recife, Pernambuco, Brazil (Rocha, Mendonça)Federal University of Piauí, Piauí, Brazil (Silva)Embrapa Semiárido, Centro de Pesquisa Agropecuaria do Tropico Semi-Árido, Brasilia, Federal District, Brazil (Veschi)
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Gilliam D, O'Brien DP, Coates JR, Johnson GS, Johnson GC, Mhlanga-Mutangadura T, Hansen L, Taylor JF, Schnabel RD. A homozygous KCNJ10 mutation in Jack Russell Terriers and related breeds with spinocerebellar ataxia with myokymia, seizures, or both. J Vet Intern Med 2014; 28:871-7. [PMID: 24708069 PMCID: PMC4238845 DOI: 10.1111/jvim.12355] [Citation(s) in RCA: 51] [Impact Index Per Article: 5.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/26/2013] [Revised: 02/14/2014] [Accepted: 03/03/2014] [Indexed: 12/21/2022] Open
Abstract
Background Juvenile‐onset spinocerebellar ataxia has been recognized in Jack Russell Terriers and related Russell group terriers (RGTs) for over 40 years. Ataxia occurs with varying combinations of myokymia, seizures, and other signs of neurologic disease. More than 1 form of the disease has been suspected. Hypothesis/Objectives The objective was to identify the mutation causing the spinocerebellar ataxia associated with myokymia, seizures, or both and distinguish the phenotype from other ataxias in the RGTs. Animals DNA samples from 16 RGTs with spinocerebellar ataxia beginning from 2 to 12 months of age, 640 control RGTs, and 383 dogs from 144 other breeds along with the medical records of affected dogs were studied. Methods This case‐control study compared the frequencies of a KCNJ10 allele in RGTs with spinocerebellar ataxia versus control RGTs. This allele was identified in a whole‐genome sequence of a single RGT with spinocerebellar ataxia and myokymia by comparison to whole‐genome sequences from 81 other canids that were normal or had other diseases. Results A missense mutation in the gene coding for the inwardly rectifying potassium channel Kir4.1 (KCNJ10:c.627C>G) was significantly (P < .001) associated with the disease. Dogs homozygous for the mutant allele all had spinocerebellar ataxia with varying combinations of myokymia and seizures. Conclusions and Clinical Importance Identification of the KCNJ10 mutation in dogs with spinocerebellar ataxia with myokymia, seizures, or both clarifies the multiple forms of ataxia seen in these breeds and provides a DNA test to identify carriers.
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Affiliation(s)
- D Gilliam
- Department of Veterinary Pathobiology, College of Veterinary Medicine, University of Missouri, Columbia, MO
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19
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Forman OP, De Risio L, Mellersh CS. Missense mutation in CAPN1 is associated with spinocerebellar ataxia in the Parson Russell Terrier dog breed. PLoS One 2013; 8:e64627. [PMID: 23741357 PMCID: PMC3669408 DOI: 10.1371/journal.pone.0064627] [Citation(s) in RCA: 51] [Impact Index Per Article: 4.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/05/2012] [Accepted: 04/11/2013] [Indexed: 11/19/2022] Open
Abstract
Spinocerebellar ataxia (SCA) in the Parson Russell Terrier (PRT) dog breed is a disease of progressive incoordination of gait and loss of balance. Clinical signs usually become notable between 6 and 12 months of age with affected dogs presenting with symmetric spinocerebellar ataxia particularly evident in the pelvic limbs. The degree of truncal ataxia, pelvic limb hypermetria and impaired balance is progressive, particularly during the initial months of disease. A certain degree of stabilisation as well as intermittent worsening may occur. At the later stages of the disease ambulation often becomes difficult, with owners often electing to euthanise affected dogs on welfare grounds. Using a GWAS approach and target-enriched massively-parallel sequencing, a strongly associated non-synonymous SNP in the CAPN1 gene, encoding the calcium dependent cysteine protease calpain1 (mu-calpain), was identified. The SNP is a missense mutation causing a cysteine to tyrosine substitution at residue 115 of the CAPN1 protein. Cysteine 115 is a highly conserved residue and forms a key part of a catalytic triad of amino acids that are crucial to the enzymatic activity of cysteine proteases. The CAPN1 gene shows high levels of expression in the brain and nervous system and roles for the protein in both neuronal necrosis and maintenance have been suggested. Given the functional implications and high level of conservation observed across species, the CAPN1 variant represents a provocative candidate for the cause of SCA in the PRT and a novel potential cause of ataxia in humans.
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Affiliation(s)
- Oliver P Forman
- Kennel Club Genetics Centre, Animal Health Trust, Kentford, Newmarket, Suffolk, United Kingdom.
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20
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Myokymia and neuromyotonia in veterinary medicine: a comparison with peripheral nerve hyperexcitability syndrome in humans. Vet J 2013; 197:153-62. [PMID: 23583699 DOI: 10.1016/j.tvjl.2013.03.002] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/16/2012] [Revised: 01/12/2013] [Accepted: 03/04/2013] [Indexed: 01/17/2023]
Abstract
Involuntary muscle hyperactivity can result from muscle or peripheral nerve hyperexcitability or central nervous system dysfunction. In humans, diseases causing hyperexcitability of peripheral nerves are grouped together under the term 'peripheral nerve hyperexcitability' (PNH). Hyperexcitability of the peripheral motor nerve can result into five different phenotypic main variants, i.e. fasciculations, myokymia, neuromyotonia, cramps and tetany, each with their own clinical and electromyographic characteristics. This review focuses on the most commonly described expressions of PNH in veterinary medicine, i.e. myokymia and neuromyotonia, in particular in young Jack Russell terriers. Data from 58 veterinary cases with generalized myokymia and neuromyotonia were analyzed, including unpublished treatment and follow-up data on eight Jack Russell terriers from a previous study and seven additional Jack Russell terriers. A dysfunction of the potassium channel or its associated proteins has been found in many human syndromes characterized by PNH, in particular in generalized myokymia and neuromyotonia, and is suspected to occur in veterinary medicine. Potential pathomechanisms of potassium channel dysfunction leading to signs of PNH are broad and include genetic mutations, antibody-mediated attack or ion channel maldistribution due to axonal degeneration or demyelination. A more accurate classification of the different PNH syndromes will facilitate a more rapid diagnosis and guide further research into natural occurring PNH in animals.
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Vanhaesebrouck A, Franklin R, Van Ham L, Bhatti S. Hereditary ataxia, myokymia and neuromyotonia in Jack Russell terriers. Vet Rec 2012; 171:131-2. [PMID: 22872628 DOI: 10.1136/vr.e5021] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/04/2022]
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Van Poucke M, Vanhaesebrouck AE, Peelman LJ, Van Ham L. Experimental validation of in silico predicted KCNA1, KCNA2, KCNA6 and KCNQ2 genes for association studies of peripheral nerve hyperexcitability syndrome in Jack Russell Terriers. Neuromuscul Disord 2012; 22:558-65. [PMID: 22342001 DOI: 10.1016/j.nmd.2012.01.008] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/22/2011] [Revised: 01/09/2012] [Accepted: 01/16/2012] [Indexed: 12/19/2022]
Abstract
KCNA1, KCNA2, KCNA6 and KCNQ2 are associated with peripheral nerve hyperexcitability in humans. In order to determine if these genes are also involved in Jack Russell Terriers with a similar syndrome characterized by myokymia and neuromyotonia, their predicted canine orthologs were first validated experimentally. They were found either incompletely or even incorrectly annotated, mainly due to gaps in the canine genomic sequence and insufficient transcript data. Canine KCNQ2 was found to contain 20 coding exons, of which three are not described in humans. It encodes for at least 14 different transcript variants in the frontal cortex of a single dog, of which only four are also described in humans. Mutation detection in Jack Russell Terriers diagnosed with peripheral nerve hyperexcitability revealed no pathogenetic relevant structural mutations. However, the four missense sequence variations and the 14 transcript variants of KCNQ2 will contribute to the study of the functional diversity of voltage-gated potassium channels.
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Affiliation(s)
- Mario Van Poucke
- Department of Nutrition, Genetics, and Ethology, Faculty of Veterinary Medicine, Ghent University, Merelbeke, Belgium.
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