The results of a search for pathogenic factors that determine the development of drug-resistant epilepsy in children are presented. The search was performed by mass parallel DNA sequencing. Pathogenic and likely pathogenic variants were detected and verified in five patients (42% of the study group). Genes in which mutations are found are associated with ion channel function, synaptic transmission, regulation of gene expression, and autophagy. De novo origin of the mutations is determined in all cases.