Goal of Study: To examine how mutations in the DHDDS gene (dehydrodolichyl diphosphate synthase) may lead to developmental delays and seizures, with or without movement issues. Key Points: The relationship between the DHDDS gene and its effects on development and seizures is still not fully understood. This study looked at how epilepsy and other developmental and movement disorders are linked to mutations in the DHDDS gene, including a detailed report on a child with these mu