Abstract：Objective To investigate the characteristics of gene mutations in unexplained infantile epileptic encephalopathy (EE).Methods A total of 47 infants with unexplained infantile EE were enrolled, and next-generation sequencing was used to analyze gene mutations in these infants and their parents.Results Of all 47 infants, 23 were found to have gene mutations, among whom 13 had de novo mutations and 10 had heterozygous mutations inherited from their father or mother. Among the 23 infants with gene mutations, 17 were found to have the gene mutations related to EE (among whom 14 had ion channel gene mutations), 2 had the gene mutations related to congenital inherited metabolic diseases, 2 had the gene mutations related to brain structural abnormality, and 2 had the gene mutations related to mental retardation.Conclusions Unexplained infantile EE may have gene mutations, mainly ion channel gene mutations.
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