Table 2.

Companion Animal Models of Movement Disorders.

Phenotype	Disease Name(s)	PathophysiologyRef	Phenotypic Trigger(s)	Affected Species; Breeds	Human Disease Analogue(s)
Hypertonicity Syndromes
	Stiff-dog-syndrome	Anti-glutamic acid decarboxylase antibodies (Pancotto and Rossmeisl, 2017)	Tactile stimulation	Canine; Beagle	Stiff-person syndrome
	Labrador hypertonicity syndrome	Unknown	Unknown	Canine; Labrador retriever	Stiff-person syndrome
Myokymia/Neuromyotonia
	Spinocerebellar ataxia, with myokymia, seizures, or both	KCNJ10 mutation (Gilliam et al., 2014) (Kir4.1 glial potassium channel)	Stress, excitement	Canine; Jack Russel Terriers and related breeds Feline	EAST SeSAME
Myotonia
	Myotonia congenita	CLCN1 mutation (Bhalerao et al., 2002; Quitt et al., 2018) (sarcolemmal chloride channel); autosomal recessive inheritance	Stiffness worse after rest; often remits after “warm up”	Canine; several breeds Feline	Myotonia congenita
Paroxysmal dyskinesias
	PD; Canine epileptoid cramping syndrome	Gluten-sensitivity (Lowrie et al., 2018)	Waking, excitement, stress, heat or cold	Canine; Border terrier	Paroxysmal non-kinesigenic dyskinesia
	PD; Episodic falling syndrome	BCAN mutation (Gill et al., 2012); autosomal recessive inheritance	Exercise, stress, or excitement	Canine; Cavalier King Charles Spaniel	PD
	PD	PIGN mutation (Kolicheski et al., 2017); autosomal recessive inheritance	Stress or excitement	Canine; Wheaten Terrier	MCASH1
	PD; Scottie cramps	Spinal cord serotonin deficiency (Geiger and Klopp, 2009); autosomal recessive inheritance	Exercise, stress, or excitement	Canine; Scottish terrier	Paroxysmal non-kinesigenic dyskinesia
	Startle disease	SLC6A5 mutation (Gill et al., 2011) (presynaptic glycine transporter); autosomal recessive inheritance	Tactile or acoustic stimulation	Canine; Irish Wolfhound	Hyperexplexia
Postural myoclonus
	Orthostatic postural myoclonus	Unknown (Garosi et al., 2005b)	Standing or posturing to eat or eliminate	Canine; Great Dane and Scottish deerhound	Orthostatic tremor

EAST = Epilepsy, ataxia, sensorineural deafness, and tubulopathy.

MCASH1 = Multiple congenital abnormalities- hypotonia-seizures syndrome 1.

PD=Paroxysmal dyskinesia.

SeSAME = Seizures, sensorineural deafness, ataxia, mental retardation, and electrolyte imbalances.