KCNE1 and KCNE2 variants in Patients with Long QT Syndrome

Introduction: Long QT syndrome (LQTS) is a type of ventricular arrhythmia characterized by prolonged QT intervals on electrocardiogram or delay in ventricular repolarization and it can lead to syncope, seizure and sudden cardiac death. Here, KCNE1 and KCNE2 variants are studied among Iranian affected families with this syndrome. Materials and Methods: Fifty patients referring to Rajaei Cardiovascular Hospital who negative for common genes were selected. Coding regions of KCNE1 and KCNE2 genes were amplified and directly sequenced to find possible variants of these genes. Bioinformatic tools were used to predict pathogenicity of the variants. Results: KCNE1 variants included c.*132A>G and c.*124A>G in 3’UTR and c.325G>A and c.112A>G in exonic regions were found. In addition, two intronic variants, c.-12-16A>G and c.-12-44C>T and two exonic variants c.170T>C and c.22A>G were observed in KCNE2 gene. Bioinformatics analysis showed pathogenicity of the variants. Conclusion: KCNE1 and KCNE2 variants have a high frequency among Iranian patients with Long QT syndrome. Therefore, study of pathogenicity of these two genes and other KCNE gene family is recommended to include in genetic tests for Iranian patients.