A novel homozygous SCN5A variant detected in sick sinus syndrome

Pacing Clin Electrophysiol. 2021 Feb;44(2):380-384. doi: 10.1111/pace.14077. Epub 2020 Oct 1.

Abstract

Sick sinus syndrome (SSS) is a group of disorders characterized by an abnormal cardiac impulse formation or propagation from the sinoatrial node. Mutated SCN5A has been reported in SSS, however, homozygosity of SCN5A is exceedingly rare. Here, we report a consanguineous family with four affected children with SSS. Symptomatic bradycardia necessitated implanting a pacemaker in all of them. Sequencing SCN5A revealed a novel homozygous variant (p.Cys1850Arg), which was predicted to interfere with protein folding. Our report describes the phenotype of a novel homozygous SCN5A variant and contributes to the compendium of molecular pathology of inherited arrhythmias in consanguineous populations.

Keywords: SCN5A; atrial standstill; electrocardiogram; sick sinus syndrome.

Publication types

  • Case Reports

MeSH terms

  • Adolescent
  • Female
  • Homozygote
  • Humans
  • Infant
  • Male
  • Mutation*
  • NAV1.5 Voltage-Gated Sodium Channel / genetics*
  • Pacemaker, Artificial
  • Pedigree
  • Sick Sinus Syndrome / genetics*
  • Sick Sinus Syndrome / therapy
  • Young Adult

Substances

  • NAV1.5 Voltage-Gated Sodium Channel
  • SCN5A protein, human