ATXN2 and Parkinson disease: Expansions were observed in patients presenting with a wide variety of overlapping clinical presentations tested with panel A (table 3, appendix p 22), including an ATXN2 repeat expansion in a patient with levodopa-responsive early-onset Parkinson's disease and a history of progressive cerebellar ataxia, and AR expansions in four patients clinically diagnosed with Charcot-Marie-Tooth disease, including one with a genetically confirmed demyelinating neuropathy (ie, Charcot-Marie-Tooth disease type 1, patient 42; appendix p 33).