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Mild paroxysmal kinesigenic dyskinesia caused by PRRT2 missense mutation with reduced penetrance.

Department of Neurology, MS Center, and Laboratory of Neuroimmunology and the Agnes-Ginges Center for Neurogenetics, Hadassah-Hebrew University Medical Center, Ein-Karem, Jerusalem, Israel.
Neurology (Impact Factor: 8.3). 08/2012; 79(9):946-8. DOI: 10.1212/WNL.0b013e318266fabf
Source: PubMed

ABSTRACT Paroxysmal kinesigenic dyskinesia (PKD) is an uncommon disorder characterized by brief episodes of involuntary dystonia or choreoathetosis triggered by sudden voluntary movement.(1) Recently, several groups identified mutations in patients with PKD in the proline-rich transmembrane protein 2 (PRRT2) gene.(2-7) We report a missense c.913G>A (p.Gly305Arg) change in PRRT2 in 4 siblings with PKD, 2 with infrequent symptoms. The association of a milder phenotype and reduced penetrance with this missense mutation suggests partial loss of function.

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