Leukoencephalopathy, Developmental Delay, and Episodic Neurologic Regression Syndrome

**Semantic type:** Disease or Syndrome

**Definition:** An autosomal dominant syndromic condition caused by mutation(s) in the EIF2AK2 gene encoding interferon-induced, double-stranded RNA-activated protein kinase. It is characterized by hypotonia, gait difficulties or ataxia, poor or absent speech with dysarthria, and variable motor abnormalities, including spasticity, dystonia, extrapyramidal signs, and tremor.

**Synonyms:** - Leuden Syndrome