Severe phenotypic spectrum of biallelic mutations in PRRT2 gene.

Background: Heterozygous dominant mutations of PRRT2 have been associated with various types of paroxysmal neurological manifestations, including benign familial infantile convulsions and paroxysmal kinesigenic dyskinesia. The phenotype associated with biallelic mutations is not well understood as few cases have been reported.

Methods: PRRT2 screening was performed by Sanger sequencing and quantitative multiplex PCR of short fluorescent fragments.