PRRT2 and episodic kinesigenic dyskinesia 1: Several previous research studies described proline-rich transmembrane protein 2 (PRRT2) as the causative gene in some nervous system diseases, including paroxysmal kinesigenic dyskinesia (PKD), infantile convulsions with PKD, benign familial infantile epilepsy (BFIE), hemiplegic migraine and episodic ataxia alone [1,2,3,4,5,6,7,8,9,10,11,12,13].