Newly discovered genetic mutation protects against Parkinson's disease and offers hope for new therapies

A previously unidentified genetic mutation in a small protein provides significant protection against Parkinson's disease and offers a new direction for exploring potential treatments, according to a new USC Leonard Davis School of Gerontology study.

The variant, located in a mitochondrial microprotein dubbed SHLP2, was found to be highly protective against Parkinson’s disease; individuals with this mutation are half as likely to develop the disease as those who do not carry it. The variant form of the protein is relatively rare and is found primarily in people of European descent.

The findings appear on January 3, 2024, in the journal Molecular Psychiatry.

First discovered by Pinchas Cohen at the USC Leonard Davis School in 2016, SHLP2 is made within the cell’s mitochondria. Previous research from the Cohen Lab established that SHLP2 is associated with protection from aging-related diseases including cancer and that levels of the microprotein change in patients with Parkinson’s disease; they rise as the body attempts to counteract the pathology of Parkinson's disease but often fail to mount additional production as the disease progresses.

This latest finding builds upon the USC team’s prior mitochondrial research and represents an advance at the intersection of longevity science, precision health, and microprotein discovery.

“This study advances our understanding of why people might get Parkinson's and how we might develop new therapies for this devastating disease,” said Cohen, professor of gerontology, medicine and biological sciences and senior author of the study. “Also, because most research is done on well-established protein-coding genes in the nucleus, it underscores the relevance of exploring mitochondrial-derived microproteins as a new approach to the prevention and treatment of diseases of aging.”

The research team was able to use targeted mass spectrometry techniques to identify the tiny peptide’s presence in neurons and found that SHLP2 specifically binds to an enzyme in mitochondria called mitochondrial complex 1. This enzyme is essential for life, and declines in its function have been linked not only to Parkinson’s disease but also to strokes and heart attacks.

“Our data highlights the biological effects of a particular gene variant and the potential molecular mechanisms by which this mutation may reduce the risk for Parkinson’s disease,” said Kim. “These findings may guide the development of therapies and provide a roadmap for understanding other mutations found in mitochondrial microproteins.”

Reference: Newly discovered genetic mutation protects against Parkinson’s disease and offers hope for new therapies; Molecular Psychiatry, DOI:10.1038/s41380-023-02344-0