Multigenerational Inheritance of Long QT Syndrome Type 2 in a Japanese Family

Intern Med. 2016;55(3):259-62. doi: 10.2169/internalmedicine.55.6014. Epub 2016 Feb 1.

Abstract

Congenital long QT syndrome (LQTS) is an important cause of sudden cardiac death in young people without any other structural disease. Mutations in the genes encoding the cardiac ion channels or associated proteins have been shown to result in ion channel dysfunction and thereby causing LQTS. We investigated a Japanese family with LQTS for four generations, with the female family members showing severe symptoms. We performed genetic tests for LQTS-related genes and identified a heterozygous KCNH2 mutation (p.K638del). In the family, the KCNH2 mutation had a very high multigenerational inheritance, and female genotype positives showed more severe phenotypes.

Publication types

  • Case Reports
  • Research Support, Non-U.S. Gov't

MeSH terms

  • Asian People / genetics*
  • Bradycardia / etiology
  • Bradycardia / genetics
  • Bradycardia / physiopathology
  • DNA Mutational Analysis
  • DNA-Binding Proteins
  • Death, Sudden, Cardiac / etiology*
  • ERG1 Potassium Channel
  • Electrocardiography
  • Ether-A-Go-Go Potassium Channels / genetics*
  • Female
  • Genetic Testing
  • Genotype
  • Humans
  • Long QT Syndrome / complications
  • Long QT Syndrome / diagnosis*
  • Long QT Syndrome / genetics*
  • Mutation / genetics*
  • Pedigree
  • Syncope / etiology
  • Syncope / genetics
  • Syncope / physiopathology

Substances

  • DNA-Binding Proteins
  • ERG1 Potassium Channel
  • Ether-A-Go-Go Potassium Channels
  • KCNH2 protein, human

Supplementary concepts

  • Long Qt Syndrome 2