Familial hemiplegic migraine, episodic ataxia type 2 (EA2), and spinocerebellar ataxia type 6 are allelic disorders of the CACNA1A gene (coding for the alpha(1A) subunit of P/Q calcium channels), usually associated with different types of mutations (missense, protein truncating, and expansion, respectively). However, the finding of expansion and missense mutations in patients with EA2 has blurr...

BACKGROUND Episodic ataxia type 2 (EA2) is an autosomal dominant condition that results from mutations in the CACNA1A gene. It is characterized by episodes of ataxia and nystagmus that typically last hours. OBJECTIVE To describe the clinical and genetic features of 2 unrelated patients who developed EA2 in childhood and late-onset dystonia. DESIGN Pedigree study. SETTING University academ...

The P/Q-type Ca(2+) channel alpha(1A) subunit gene (CACNA1A) was cloned on the short arm of chromosome 19 between the markers D19S221 and D19S179 and found to be responsible for Episodic Ataxia type 2, Familial Hemiplegic Migraine and Spinocerebellar Ataxia type 6. This region was physically mapped by 11 cosmid contigs spanning about 1. 4Mb, corresponding to less than 70% of the whole region. T...

Episodic ataxia (EA) is an autosomal dominant human disorder that produces persistent myokymia and attacks of generalized ataxia. Recently, familial EA has been linked to the voltage-dependent delayed rectifier, Kv1.1, on chromosome 12. Six EA families have been identified that carry distinct Kv1.1 missense mutations; all individuals are heterozygous. Expression in Xenopus oocytes demonstrates ...

Episodic ataxia type 2 (EA2) is an inherited autosomal dominant disorder related to cerebellar dysfunction and is associated with mutations in the pore-forming alpha(1A)-subunits of human P/Q-type Ca(2+) channels (Cav2.1 channels). The majority of EA2 mutations result in significant loss-of-function phenotypes. Whether EA2 mutants may display dominant-negative effects in human, however, remains...

PRRT2 pathogenic variants have been described in benign familial infantile epilepsy, episodic ataxia, paroxysmal kinesigenic dyskinesia, and hemiplegic migraines. We describe a patient with compound heterozygous variants, infantile epilepsy with status epilepticus, paroxysmal dyskinesia and episodic ataxia. Testing revealed a pathogenic PRRT2 duplication (c.649dupC), and a likely pathogenic mis...

CONTEXT Although phenotypic heterogeneity in autosomal dominant spinocerebellar ataxia (SCA) has been explained in part by genotypic heterogeneity, clinical observations suggest the influence of additional factors. OBJECTIVES To demonstrate, quantitate, and localize physiologic abnormalities attributable to nongenetic factors in the development of hereditary SCA. DESIGN Quantitative assessm...

A 20-year-old man presented with vertigo followed by hourly episodes of dysarthria and incoordination lasting 5–20 seconds (video 1). Neurologic examination was normal between episodes. The only brain/spine MRI lesion in the right superior cerebellar peduncle (figure, A). CSF analysis revealed elevated white blood cells (6/?L [normal, 0–5]) oligoclonal bands (?4). Paroxysmal dysarthria–ataxia a...

Ataxia can be classified according to the onset into episodic, acute, intermittent and chronic ataxia. Acute ataxia in children is caused by CNS tumors, trauma, CNS infection, toxins, metabolic causes or stroke. Recurrent ataxia can be due to metabolic causes, seizures, basilar artery migraine or toxins. Chronic ataxia is usually the result of hereditary ataxia, CNS tumors, congenital anomalies...