Paroxysmal Dyskinesia

Gene: SCN8A

Green List (high evidence)

PMID: 26677014 (2016)
3 families 16 individuals, cosegregating het missense SCN8A:c.4447G>A; p.E1483K (founder effect excluded by linkage analysis). All patients had seizures (15/16 individuals seizures in first to second year of life, 1/16 seizures at school age). 5/16 patients developed additional brief paroxysmal episodes in puberty, either dystonic/dyskinetic or "shivering" attacks, triggered by stretching or motor initiation (3 patients from 2 families), or emotional stimuli (2 patients who were both from the same family).

PMID: 29356177 (2018)
De novo SCN8A mutation c.3640G>A (p.A1214T) in 23M with PKD

PMID: 25799905 (2015)
De novo dominant SCN8A (c.3979A>G; p.Ile1327Val) in male with in utero onset of movement disorder (exaggerated startle, paroxysmal posturing and jittery movements subsiding in sleep that on clinical and encephalographic grounds were not epileptic in nature), with evolving epilepsy, epileptic encephalopathy and developmental delay

Created: 2 May 2024, 7:19 a.m. | Last Modified: 2 May 2024, 7:20 a.m.

Panel Version: 0.125

Mode of inheritance
MONOALLELIC, autosomal or pseudoautosomal, NOT imprinted

Phenotypes
Complex neurodevelopmental disorder MONDO:0100038

Publications

• 26677014
• 29356177
• 25799905

Variants in this GENE are reported as part of current diagnostic practice