In LGI1 antibody disease, parkinsonism and limb dystonia are observed,8 15 whereas orthostatic myoclonus is more suggestive of CASPR2 antibodies.31 Overall, these movement disorders are very rarely seen in isolation, and their presence alongside amnesia or focal seizures should highlight LGI1 or CASPR2 antibodies in the differential diagnosis. The gene discussed is CNTNAP2; the disease is glycogen storage disease VI.