Identification of gene mutations in patients with primary periodic paralysis using targeted next-generation sequencing

BACKGROUND: Primary periodic paralysis is characterized by recurrent quadriplegia typically associated with abnormal serum potassium levels. The molecular diagnosis of primary PP previously based on Sanger sequencing of hot spots or exon-by-exon screening of the reported genes. METHODS: We developed a gene panel that includes 10 ion channel-related genes and 245 muscular dystrophy- and myopathy-related genes and used this panel to diagnose 60 patients with primary periodic paralysis and identify the disease-causing or risk-associated gene mutations. RESULTS: Mutations of 5 genes were discovered in 39 patients (65.0%). SCN4A, KCNJ2 and CACNA1S variants accounted for 92.5% of the patients with a genetic diagnosis. CONCLUSIONS: Targeted next-generation sequencing offers a cost-effective approach to expand the genotypes of primary periodic paralysis. A clearer genetic profile enables the prevention of paralysis attacks, avoidance of triggers and the monitoring of complications. ELECTRONIC SUPPLEMENTARY MATERIAL: The online version of this article (10.1186/s12883-019-1322-6) contains supplementary material, which is available to authorized users.