Biallelic inherited <i>SCN8A</i> variants, a rare cause of <i>SCN8A</i>‐related developmental and epileptic encephalopathy

Abstract

These studies demonstrate that SCN8A DEE may, in rare cases, result from inheritance of two variants, both of which exhibit reduced channel activity. In these families, heterozygosity for the dominant variants results in less severe disease than biallelic inheritance of two variant alleles. The clinical consequences of variants with partial and complete loss of SCN8A function are variable and likely to be influenced by genetic background.