OMIA:000689-9913 : Hyperekplexia, GLRA1-related in Bos taurus (taurine cattle)

In other species: dog , horse

Categories: Nervous system phene

Links to possible relevant human trait(s) and/or gene(s) in OMIM: 149400 (trait) , 138491 (gene)

Links to relevant human diseases in MONDO:

Mendelian trait/disorder: yes

Mode of inheritance: Autosomal recessive

Considered a defect: yes

Key variant known: yes

Year key variant first reported: 2001

Cross-species summary: renamed from 'myoclonus' to 'hyperekplexia, GLRA1-related' [27/5/2023]

Species-specific name: inherited myoclonus; congenital myoclonus; neuraxial (o)edema

Molecular basis: By cloning and sequencing a very likely comparative candidate gene (based on the homologous disorder in humans and mice), Pierce et al. (2001) identified a causal mutation as a "a cytidine to adenine transversion at position 156 of the Glra1 gene (156C>A). The 156A allele is predicted to substitute a termination codon for a tyrosine codon (Y24*) in exon 2 . . . This substitution is predicted to result in a prematurely truncated protein that lacks ligand-binding and membrane-spanning domains".

Breed: Polled Hereford (Cattle) (VBO_0000341).
Breeds in which the phene has been documented. (If a likely causal variant has been documented for the phene, see the variant table breeds in which the variant has been reported).

Associated gene:

Symbol Description Species Chr Location OMIA gene details page Other Links
GLRA1 glycine receptor alpha 1 Bos taurus 7 NC_037334.1 (63108191..63021619) GLRA1 Homologene, Ensembl , NCBI gene


By default, variants are sorted chronologically by year of publication, to provide a historical perspective. Readers can re-sort on any column by clicking on the column header. Click it again to sort in a descending order. To create a multiple-field sort, hold down Shift while clicking on the second, third etc relevant column headers.

WARNING! Inclusion of a variant in this table does not automatically mean that it should be used for DNA testing. Anyone contemplating the use of any of these variants for DNA testing should examine critically the relevant evidence (especially in breeds other than the breed in which the variant was first described). If it is decided to proceed, the location and orientation of the variant sequence should be checked very carefully.

Since October 2021, OMIA includes a semiautomated lift-over pipeline to facilitate updates of genomic positions to a recent reference genome position. These changes to genomic positions are not always reflected in the ‘acknowledgements’ or ‘verbal description’ fields in this table.

OMIA Variant ID Breed(s) Variant Phenotype Gene Allele Type of Variant Source of Genetic Variant Reference Sequence Chr. g. or m. c. or n. p. Verbal Description EVA ID Year Published PubMed ID(s) Acknowledgements
302 Polled Hereford (Cattle) Myoclonus GLRA1 nonsense (stop-gain) Naturally occurring variant ARS-UCD1.2 7 g.63070074G>T c.156C>A p.(Y52*) 2001 11178872 Variant coordinates obtained from or confirmed by EBI's Some Effect Predictor (VEP) tool; Breed information kindly provided or confirmed by Matt McClure and Jennifer McClure from "Understanding Genetics and Complete Genetic Disease and Trait Definition (Expanded 2016 Edition)" (

Cite this entry

Nicholas, F. W., Tammen, I., & Sydney Informatics Hub. (2023). OMIA:000689-9913: Online Mendelian Inheritance in Animals (OMIA) [dataset].


Note: the references are listed in reverse chronological order (from the most recent year to the earliest year), and alphabetically by first author within a year.

2021 Konovalova, E., Romanenkova, O., Kostyunina, O., Gladyr, E. :
The molecular bases study of the inherited diseases for the health maintenance of the beef cattle. Genes (Basel) 12:678, 2021. Pubmed reference: 33946496. DOI: 10.3390/genes12050678.
2011 Windsor, P., Kessell, A., Finnie, J. :
Neurological diseases of ruminant livestock in Australia. V: congenital neurogenetic disorders of cattle. Aust Vet J 89:394-401, 2011. Pubmed reference: 21933167. DOI: 10.1111/j.1751-0813.2011.00826.x.
2006 Schulze, U., Wohlke, A., Drogemoller, C., Marxfeld, H., De Vries, F., Baumgartner, W., Distl, O. :
[Case report: congenital myoclonus in a German Holstein calf]. Dtsch Tierarztl Wochenschr 113:203-6, 2006. Pubmed reference: 16821565.
2002 Healy, P.J., Dennis, J.A., Windsor, P.A., Pierce, K.D., Schofield, P.R. :
Genotyping cattle for inherited congenital myoclonus and maple syrup urine disease Australian Veterinary Journal 80:695-697, 2002. Pubmed reference: 12465829.
2001 Pierce, K.D., Handford, C.A., Morris, R., Vafa, B., Dennis, J.A., Healy, P.J., Schofield, P.R. :
A nonsense mutation in the alpha1 subunit of the inhibitory glycine receptor associated with bovine myoclonus. Mol Cell Neurosci 17:354-63, 2001. Pubmed reference: 11178872. DOI: 10.1006/mcne.2000.0934.
2000 Nguyen, BQ., Kanthasamy, AG., Truong, DD. :
Animal models of myoclonus: an overview. Mov Disord 15 Suppl 1:22-5, 2000. Pubmed reference: 10755268.
1990 Gundlach, A.L. :
Disorder of the inhibitory glycine receptor - inherited myoclonus in Poll Hereford calves. FASEB Journal 4:2761-2766, 1990. Pubmed reference: 2165010.
Lummis, S.C.R., Gundlach, A.L., Johnston, G.A.R., Harper, P.A.W., Dodd, P.R. :
Increased gamma-aminobutyric acid receptor function in the cerebral cortex of myoclonic calves with an hereditary deficit in glycine strychnine receptors. Journal of Neurochemistry 55:421-426, 1990. Pubmed reference: 2164565.
1989 Luscombe, G.P. :
Animal models of myoclonus. Disorders of movement : clinical, pharmacological and physiological aspects (eds N.P. Quinn and P.G. Jenner), Academic Press, London :445-454, 1989.
Tadich, N., Cubillos, V., Wittwer, F. :
Neuraxial oedema of a Hereford calf without hypomyelinogenesis. Archivos de Medicina Veterinaria 21:167-172, 1989.
1988 Gundlach, A.L., Dodd, P.R., Grabara, C.S.G., Watson, W.E.J., Johnston, G.A.R., Harper, P.A.W., Dennis, J.A., Healy, P.J. :
Deficit of spinal cord glycine/strychnine receptor in inherited myoclonus of Polled Hereford calves Science 241:1807-1810, 1988. Pubmed reference: 2845573.
1987 Healy, P.J., Dennis, A.J., Harper, P.A.W., Heath, T.D. :
Determination of the congenital myoclonus genotype of bulls by multiple ovulation-embryo transfer Australian Veterinary Journal 64:224-225, 1987. Pubmed reference: 3675417.
1986 Harper, PA., Healy, PJ., Dennis, JA. :
Inherited congenital myoclonus of polled Hereford calves (so-called neuraxial oedema): a clinical, pathological and biochemical study. Vet Rec 119:59-62, 1986. Pubmed reference: 3750776.
1984 Morrow, C.J. :
Hereditary neuraxial oedema of Hereford cattle. Aust Vet J 61:414, 1984. Pubmed reference: 6534366.
1980 Chick, B.F., Clarke, F.L., Chambers, S. :
Neuraxial oedema of polled Hereford calves New South Wales Veterinary Proceedings 16:62-65, 1980.
1978 Cho, D.Y., Leipold, H.W. :
Hereditary neuraxial edema in polled Hereford calves Pathology Research and Practice 163:158-162, 1978.
1974 Weaver, A.D. :
Hereditary neuraxial oedema in polled Hereford calves Deutsche Tierarztliche Wochenschrift 81:572-573, 1974. Pubmed reference: 4611727.

Edit History

  • Created by Frank Nicholas on 15 Nov 2005
  • Changed by Frank Nicholas on 09 Dec 2011
  • Changed by Frank Nicholas on 18 Sep 2012
  • Changed by Frank Nicholas on 29 Sep 2013
  • Changed by Frank Nicholas on 16 Aug 2016
  • Changed by Imke Tammen2 on 14 Jul 2021
  • Changed by Imke Tammen2 on 27 May 2023