Co-Existing Charcot-Marie-Tooth Disease Type II and Parkinson’s Disease Linked to a Novel DNAjB2 Pathogenic Variant

Background: The DNAjB2 gene encodes a co-chaperone protein that interacts with the heat shock protein (HSP) family to maintain protein quality control and preserve neuronal integrity. Variants in this gene have been associated with the axonal form of Charcot-Marie-Tooth Disease (CMT2). Recent literature has also suggested an association between DNAjB2 variants and neurodegenerative disorders such as Parkinson’s disease (PD). Design/Methods: Case Report. Case Description: We present a 36-year-old female patient initially diagnosed with CMT2 at the age of 28, who later developed symptoms of PD in her fourth decade. Genetic test revealed compound heterozygous pathogenic variants in DNAjB2 (c.352+1 G>A and c.175+2T>A). Conclusion: To our knowledge, this is the first case report describing the dual phenotype of CMT2 and young-onset PD linked to compound heterozygosity in DNAjB2. The dual dysfunction of axonal degeneration and dopaminergic neuron loss suggests that DNAjB2 plays a pivotal role in maintaining proteostasis in both the peripheral and central nervous systems.