Importance of targeted next-generation sequencing in pediatric patients with developmental epileptic encephalopathy

Rev Assoc Med Bras (1992). 2023 Oct 9;69(10):e20230547. doi: 10.1590/1806-9282.20230547. eCollection 2023.

Abstract

Objective: Childhood epilepsy is a common neurological disorder with a prevalence of 300-600 cases per 100,000 people. It is associated with refractory epilepsies, global developmental delay, and epileptic encephalopathies, causing epileptic syndromes characterized by cognitive and behavioral disorders.

Methods: In this retrospective cohort study, patients with refractory epilepsy and global developmental delay, defined as epileptic encephalopathy, who applied to the Aydın 7Maternity and Children's Hospital Genetic Diagnosis Center and were followed in the pediatric neurology clinic of our hospital, between July 2018 and July 2021, were included.

Results: Targeted next-generation sequencing molecular genetics results were reviewed, and 3 ALDH7A1, 1 AARS, 3 CACNA1A, 1 CTNNB1, 1 DCX, 2 DBH, 2 DOCK7, 1 FOLR1, 2 GABRB3, 2 GCH1, 1 VGRIN2B, 1 GUF1, 3 KCNQ2, 2 KCNT1, 1 NECAP1, 1 PCDH19, 1 PNPO, 1 SCN8A, 1 SCN9A, 4 SCN1A, 2 SLC25A22, 1 SLC2A1, 2 SPTAN1, 2 SZT2, 4 TBC1D24, 2 TH, and 1 PCDH19 (X chromosome) mutations were detected in three of the patients using the next-generation sequencing method.

Conclusion: Although the development of gene panels aids in diagnosis, there are still unidentified disorders in this illness category, which is highly variable in genotype and phenotype. Understanding the genetic etiology is vital for genetic counseling and, maybe, the future development of remedies for the etiology.

MeSH terms

  • Child
  • Epilepsy* / genetics
  • Folate Receptor 1 / genetics
  • Genotype
  • High-Throughput Nucleotide Sequencing
  • Humans
  • Mitochondrial Membrane Transport Proteins / genetics
  • Mutation
  • NAV1.7 Voltage-Gated Sodium Channel / genetics
  • Phenotype
  • Protocadherins
  • Retrospective Studies

Substances

  • FOLR1 protein, human
  • Folate Receptor 1
  • SLC25A22 protein, human
  • Mitochondrial Membrane Transport Proteins
  • SCN9A protein, human
  • NAV1.7 Voltage-Gated Sodium Channel
  • PCDH19 protein, human
  • Protocadherins
  • TBC1D24 protein, human
  • SZT2 protein, human
  • KCNT1 protein, human