Likewise, variants in another member of the mtDNA replication complex, C10orf2, can lead to an ataxia‐neuropathy syndrome that includes dementia.17 Parkinsonism is a clinical feature of the neurological syndrome described here that is not commonly reported in conjunction with multiple mtDNA deletions, however, variants in POLG,18, 19C10orf2,20OPA1,21 and MPV1722 have been associated with neurological syndromes that include parkinsonism as a component. Here, POLG is linked to Parkinson disease.