Resolving 'vascular parkinsonism' -COL22A1 as a genetic adult-onset leukoencephalopathy.

We describe an elderly woman meeting criteria for vascular parkinsonism/dementia associated with a likely pathogenic variant in the COL22A1 gene, supported by functional experiments in a zebrafish model. We suggest that white matter hyperintensities may not represent small-vessel ischemic disease and that, if confirmed by further observations, COL22A1 may be included among the adult-onset leukoencephalopathies mislabeled as "vascular parkinsonism."