This study aimed to test the hypothesis that suppression of the occurrence of absence seizures and depression-like comorbidity in WAG/Rij offspring caused by a maternal methyl-enriched diet may be associated with modification of the DNA methyltransferase 1 (DNMT1), HCN1, and tyrosine hydroxylase (TH) gene expression. The gene discussed is HCN1; the disease is major depressive disorder.