Biallelic DNAJC12 mutations were described in children with hyperphenylalaninemia, neurodevelopmental delay, and dystonia.
We identified DNAJC12 homozygous null variants (c.187A>T;p.K63*and c.79-2A>G;p.V27Wfs*14) in two kindreds with early-onset parkinsonism. Both probands had mild intellectual disability, mild non-progressive, motor symptoms, sustained benefit from small dose of levodopa and substantial worsening of symptoms after levodopa discontinuation. Neuropathology (Proband-A) revealed no alpha-synuclein pathology and substantia nigra depigmentation with moderate cell loss DNAJC12 transcripts were reduced in both patients. Our results suggest DNAJC12 mutations (absent in 500 early-onset patients with Parkinson’s disease) rarely cause dopa-responsive non-progressive parkinsonism in adulthood, broadening the clinical spectrum of DNAJC12 deficiency. This article is protected by copyright. All rights reserved.