Objective: This work aims to develop and evaluate novel nonviral CRISPR-based genome editing strategies to achieve precise and durable transcriptional modulation of SNCA, enabling controlled α-synuclein (αSyn) reduction as a potential therapeutic approach for Parkinson’s disease and related α-synucleinopathies.

Background: Neurodegenerative diseases, including Parkinson’s disease (PD), are projected to become leading causes of death and disability worldwide and are expected to surpass cancer-related deaths by the year of 2040 (1). Human genetic evidence demonstrates that increased αSyn expression elevates disease risk, whereas reduced expression appears protective (2, 3). There remains a critical unmet need for therapeutic strategies that durably lower αSyn to a protective level in neurons without inducing harmful loss-of-function effects. While prior approaches have achieved αSyn reduction (4–19), there is currently no nonviral CRISPR-based strategy that enables precise transcriptional downregulation of endogenous αSyn for controlled, moderate suppression of αSyn.

Method: Regulatory architecture, including known motifs of transcription factors which have been implicated to contribute to αSyn expression, within the SNCA locus were investigated and genome editing strategies were developed to the regulation of αSyn expression in human iPSC-derived neurons. Resulting changes in α-synuclein expression quantified using RT-qPCR, Western blotting, and ELISA based techniques. Editing approaches aimed to precisely perturb specific regulatory architecture to tune endogenous gene output rather than ablating the gene, thus aiming to reduce pathological burden while preserving essential physiological function.

Results: Genome editing strategies which target the transcriptional modulation of SNCA produced measurable and reproducible reductions in αSyn expression in human iPSC-derived neurons, verified by molecular and protein analyses. These findings support the feasibility of precise transcriptional modulation as a strategy for controlled αSyn reduction.

Conclusion: Experimental results demonstrate that precision genome editing can be leveraged to durably modulate endogenous αSyn expression in human neuronal models and provides a potential framework toward the development of disease-modifying therapeutic strategies for Parkinson’s disease and related α-synucleinopathies.

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MDS Abstracts - https://www.mdsabstracts.org/abstract/a-novel-genome-editing-strategy-for-permanent-and-precise-downregulation-of-%ce%b1-synuclein-in-parkinsons-disease/