Calmodulin Interacting Genes as a Novel Candidate for Pathogenesis of Long-QT Syndrome

Background: Approximately 30% of long-QT syndrome (LQTS) cases remains genetically elusive. Here, we investigated usefulness of the whole exon sequencing (WES) by next-generation sequencing for identification of novel pathogenic candidates which directly or indirectly interact with proteins encoded by known LQTS genes. Methods: Of 1815 Japanese LQTS cohort patients, WES was performed in 59 LQTS patients and 61 unaffected individuals from 35 families and 138 unrelated LQTS cases, all were screened major LQTS genes such as KCNQ1, KCNH2, SCN5A, KCNE1, KCNE2 and KCNJ2. After WES, the genes known as inherited arrhythmias were screened by the Human Gene Mutation Database, and the Sanger sequencing was also referred for validation of the mutations and common variants were excluded by the public (1000G, ESP6500 and dbSNP) and Riken database. Results: Total 92 candidate mutations including 11 de novo, 5 recessive (2 homozygous and 3 compound heterozygous) and 73 dominant mutations in 88 genes were identified in 23...