Natural History Study of ATP1A3-related Disease

Inclusion Criteria: * Children and adults of any age carrying a mutation in the ATP1A3-gene. * Children and adults of any age matching an ATP1A3-related disease phenotype without a mutation in the gene. * Written informed consent given by patient and/or parent/guardian. Exclusion Criteria: • Patients with a phenotype not fitting ATP1A3-related disease and no mutation in the ATP1A3 gene.