Distinct changes in about a quarter of gut microbial species among carriers of the GBA1 gene variant, a known Parkinson’s disease risk factor, could help predict the neurodegenerative condition before symptoms appear, reveals a new analysis published in Nature Medicine.
Researchers from University College London analyzed fecal samples and clinical data from 271 Parkinson’s patients, 43 asymptomatic GBA1 carriers, and 150 healthy controls in the UK and Italy. They identified 176 microbial species differing between healthy individuals and those with Parkinson’s, with over 140 showing consistent shifts in carriers.
These carriers displayed an intermediate microbiome profile between healthy and diseased groups, correlating with early non-motor symptoms like gastrointestinal issues, which often precede motor symptoms after significant neuron loss.
The pattern held in validation cohorts from the US, South Korea, and Turkey (638 Parkinson’s cases, 319 healthy), suggesting gut microbiome alterations mark the prodromal phase and incomplete penetrance of GBA1 variants.
While cross-sectional, the findings bolster the gut-brain axis theory in Parkinson’s pathogenesis, where dysbiosis may contribute to early neuron damage via gastrointestinal dysfunction like constipation and gastroparesis.
Experts note this microbial signature could enable early interventions, such as microbiome-modulating diets or therapies, to delay onset, though longitudinal studies are needed to confirm predictive power.
