Similarly, a translocation mutation within the ARHGEF9 gene has been shown to result in a neurodevelopmental syndrome that includes epilepsy, anxiety, aggressive behavior, sleep–wake disruptions, and mental retardation, but not hyperekplexia24,26,27, suggesting a broad disruption of GABAergic but not glycinergic signaling in this variant of the disorder. The gene discussed is ARHGEF9; the disease is epilepsy.