KCNT2 and Epileptic encephalopathy: Whole-exome sequencing to identify likely pathogenic variants in KCNT2 causing developmental and epileptic encephalopathies (DEEs). Retrospective collection and analysis of clinical data. Confirmation of variants using conventional Sanger sequencing. Pathogenicity analysis using PolyPhen-2 and MutationTaster. Classification of variants as likely pathogenic based on the American College of Medical Genetics (ACMG) guidelines