14q12 duplication including FOXG1: is there a common age-dependent epileptic phenotype?

Brain Dev. 2014 May;36(5):402-7. doi: 10.1016/j.braindev.2013.06.008. Epub 2013 Jul 6.

Abstract

Introduction: Duplications of 14q12 encompassing FOXG1 gene have been recently associated with developmental delay, severe speech impairment, epilepsy, aspecific neuroimaging findings and minor dysmorphisms.

Aim and methods: In order to refine the epileptic phenotype associated with 14q12 duplications, we have performed a review of the electroclinical picture of the patients reported to date in the literature, adding a new personal case. A comprehensive set of clinical and instrumental data (with a particular focus on the electroclinical aspects including seizure type, age of onset, EEG at onset and after antiepileptic therapy, drug efficacy) has been taken into account.

Results: 9/14 patients carrying 14q12 duplications developed seizures, all in the first months of life. Most of them developed infantile spasms (8/9 epileptic patients) and presented hypsarrhythmia or modified hypsarrhythmia on EEG. After therapy 5/9 patients became seizure free and 3/9 present a good seizure control. At last available follow up, 2/3 of the epileptic patients displayed an almost normal EEG, or a quite organized background activity, with diffuse or focal (mostly temporal) slowing.

Conclusions: The review of the available data allowed to recognize a common epileptic core, characterized by early onset, age dependent epileptic encephalopathy with infantile spasms and typical, atypical or modified hypsarrhythmia. Antiepileptic therapy soon led to a good or complete control of seizures with a nearly normal background activity in most patients.

Keywords: 14q12 duplication; Epileptic encephalopathy; FOXG1; Infantile spasms.

Publication types

  • Case Reports
  • Review

MeSH terms

  • Age of Onset
  • Brain / drug effects
  • Brain / physiopathology
  • Chromosome Duplication*
  • Chromosomes, Human, Pair 14*
  • Electroencephalography
  • Epilepsy / drug therapy
  • Epilepsy / genetics*
  • Epilepsy / physiopathology*
  • Face / pathology
  • Female
  • Follow-Up Studies
  • Forkhead Transcription Factors / genetics*
  • Humans
  • Infant
  • Nerve Tissue Proteins / genetics*
  • Phenotype

Substances

  • FOXG1 protein, human
  • Forkhead Transcription Factors
  • Nerve Tissue Proteins