Monarch Disease Ontology term MONDO_0007087 (alternating hemiplegia of childhood 1) is any alternating hemiplegia of childhood in which the cause of the disease is a mutation in the ATP1A2 gene. Also known as: ATP1A2 alternating hemiplegia of childhood, alternating hemiplegia of childhood caused by mutation in ATP1A2, alternating hemiplegia of childhood type 1.