Whole-exome sequencing identifies a novel mutation (R367G) in SCN5A to be associated with familial cardiac conduction disease

Cardiac conduction disease is a primary cause of sudden cardiac death. Sodium voltage‑gated channel‑α subunit 5 (SCN5A) mutations have been reported to underlie a variety of inherited arrhythmias. Numerous disease‑causing mutations of SCN5A have been identified in patients with ≥10 different conditions, including type 3 long‑QT syndrome and Brugada syndrome. The present study investigated a family with a history of arrhythmia, with the proband having a history of arrhythmia and syncope. Whole‑exome sequencing was applied in order to detect the disease‑causing mutation in this family, and Sanger sequencing was used to confirm the co‑segregation among the family members. A missense mutation (c.1099C>G/p.R367G) of SCN5A was identified in the family and was observed to be co‑segregated in all affected members of the family. The missense mutation results in a substitution of glycine for arginine, which may affect sodium transmembrane transport. The present study provides an accurate genetic test which may be used in individuals who exhibit no clinical symptoms.