GAMT and hyperinsulinemic hypoglycemia, familial, 4: Energy deficiency can cause seizures in various metabolic disorders including mitochondrial diseases, glucose transporter type 1 (GLUT-1) deficiency, guanidinoacetate methyltransferase (GAMT) deficiency, and disorders causing hypoglycemia including fatty acid oxidation defects, disorders of gluconeogenesis, and glycogen storage disorders (Table 1).