Discovery of DNA methylation signature in the peripheral blood of individuals with history of antenatal exposure to valproic acid

Genet Med. 2024 Oct;26(10):101226. doi: 10.1016/j.gim.2024.101226. Epub 2024 Jul 31.

Abstract

Purpose: Valproic acid or valproate is an effective antiepileptic drug; however, embryonic exposure to valproate can result in a teratogenic disorder referred to as fetal valproate syndrome (OMIM #609442). Currently there are no diagnostic biomarkers for the condition. This study aims to define an episignature biomarker for teratogenic antenatal exposure to valproate.

Methods: DNA extracted from peripheral blood of individuals with teratogenic antenatal exposure to valproate was processed using DNA methylation microarrays. Subsequently, methylation profiling and construction of support vector machine classifiers were performed in R.

Results: Genomic DNA methylation analysis was applied, and a distinct DNA methylation profile was identified in the majority of affected individuals. This profile was used to develop a diagnostic episignature classifier. The valproate exposure episignature exhibited high sensitivity and specificity relative to a large reference data set of unaffected controls and individuals with a wide spectrum of syndromic disorders with episignatures. Gene set enrichment analysis demonstrated an enrichment for terms associated with cell adhesion, including significant overrepresentation of the cadherin superfamily.

Conclusion: This study provides evidence of a robust peripheral blood-based diagnostic epigenetic biomarker for a prenatal teratogenic disorder.

Keywords: DNA methylation; Epigenetics; Episignature; Fetal valproate syndrome; Teratogens.

MeSH terms

  • Abnormalities, Drug-Induced
  • Anticonvulsants / adverse effects
  • Biomarkers / blood
  • DNA Methylation* / genetics
  • Epigenesis, Genetic
  • Female
  • Humans
  • Male
  • Pregnancy
  • Prenatal Exposure Delayed Effects / blood
  • Prenatal Exposure Delayed Effects / chemically induced
  • Prenatal Exposure Delayed Effects / genetics
  • Valproic Acid* / adverse effects

Substances

  • Valproic Acid
  • Anticonvulsants
  • Biomarkers

Supplementary concepts

  • Valproic acid antenatal infection