Category: Parkinson's Disease: Genetics
Objective: We describe two sisters with late-onset parkinsonism associated with a CCDC88C variant (p.R464H).
Background: Tsoi et al. (2014) identified a heterozygous missense mutation in the CCDC88C gene (R464H), by combining linkage analysis and whole-exome sequencing in a Chinese family, in which 5 individuals had adult-onset spinocerebellar ataxia.
Method: Case report.
Results: We report two sisters with late-onset parkinsonism associated with a CCDC88C variant (p.R464H). Both siblings underwent detailed neurological examinations. Whole-genome sequencing was performed in the elder sister. The younger sister presented with pure parkinsonism without ataxia and with a slow progression in the past 16 years. Brain magnetic resonance imaging was normal, and there was no cerebellar atrophy. The first symptom of elder sister was rest tremor in the right upper limb at 74 years old, and a clinical diagnosis of PD two years later. DAT-PET scan showed a significant reduction in DAT binding in bilateral putamen (more pronounced on the left), and FDG-PET imaging showed a relative bilateral thalamus hypometabolism. Genetic testing showed both sisters were heterozygous for R464H variant in CCDC88C.
Conclusion: Our findings suggest the extension of the CCDC88C variant (p.R464H) associated phenotype to include late-onset parkinsonism.
To cite this abstract in AMA style:
Z. Lin, W. Luo. CCDC88C p.R464H likely cause a novel late-onset parkinsonism phenotype [abstract]. Mov Disord. 2022; 37 (suppl 2). https://www.mdsabstracts.org/abstract/ccdc88c-p-r464h-likely-cause-a-novel-late-onset-parkinsonism-phenotype/. Accessed June 15, 2025.« Back to 2022 International Congress
MDS Abstracts - https://www.mdsabstracts.org/abstract/ccdc88c-p-r464h-likely-cause-a-novel-late-onset-parkinsonism-phenotype/