MedGen

X-linked epilepsy-1 with variable learning disabilities and behavior disorders (EPILX1) is an X-linked neurologic disorder characterized by the onset of complex partial seizures in the first or second decades. The seizures are often triggered by showering or water-related hygiene activities, consistent with reflex bathing epilepsy. Additional spontaneous seizures and secondary generalization may also occur. Most patients have associated developmental defects, including learning disabilities, behavioral problems, or autistic features. The pathophysiology of the reflex seizures is thought to be hyperexcitability of the cortical or subcortical neuronal areas that respond to physiologic stimulus in an exaggerated manner, possibly due to aberrant synaptic maturation (summary by Nguyen et al., 2015; Sirsi et al., 2017; Accogli et al., 2021). [from OMIM]

X-linked intellectual developmental disorder-50 (XLID50) is a neurodevelopmental disorder characterized by impaired intellectual development accompanied variably by short stature, autistic features, and brain imaging anomalies. Seizures are not present. Carrier females may be affected. Hemizygous mutation in the SYN1 gene also causes X-linked epilepsy with variable learning disabilities and behavior disorders (EPILX1; 300491), which shows overlapping features. [from OMIM]