Hyperekplexia 4, also known as hkpx4, is related to hypertonia and early infantile epileptic encephalopathy. An important gene associated with Hyperekplexia 4 is ATAD1 (ATPase Family AAA Domain Containing 1), and among its related pathways/superpathways are Neuropathic Pain-Signaling in Dorsal Horn Neurons and Neuroscience. Affiliated tissues include eye, and related phenotypes are seizure and inguinal hernia