Researchers at the Germans Trias i Pujol Research Institute (IGTP) report that blood platelets could provide a sensitive way to monitor molecular changes as Parkinson’s disease progresses. The findings, published in Movement Disorders, are based on longitudinal analysis of gene expression in a patient with a rare SNCA gene triplication whose condition advanced from early motor symptoms to dementia over three years.
The patient carried a non-inherited, 2.41-megabase triplication on chromosome 4q22.1 covering 21 genes, including SNCA, which encodes alpha-synuclein. Researchers analyzed whole blood and purified platelets at age 41, during the early motor phase, and again at age 44, after dementia had developed.
Whole-blood samples showed relatively few changes between the two stages. Platelets, however, displayed broader transcriptomic alterations involving mitochondrial respiration, protein translation and inflammatory signaling. These findings suggest that platelet RNA may reflect disease-associated biological shifts more clearly than standard whole-blood testing.
The researchers then examined selected genes in an independent group of 15 people with sporadic early-onset Parkinson’s disease and 18 healthy controls. Several changes identified in the rare genetic case were also observed in this group, including reduced expression of a specific SNCA RNA isoform and YWHAB, a gene related to the 14-3-3 protein family, as well as increased expression of MMRN1, which encodes the platelet- and endothelial-associated protein multimerin-1.
The differences remained significant in purified platelets after correction for multiple comparisons. The same patients’ whole-blood samples did not show statistically detectable differences from those of healthy controls.
The study’s authors say the overlap between the rare SNCA-related case and sporadic Parkinson’s disease may point to biological mechanisms shared across different forms of the condition. Platelets are of interest as a peripheral model because they contain mitochondria, store signaling molecules and express substantial levels of alpha-synuclein.
The researchers caution that the longitudinal analysis involved only one patient, so the findings represent a proof of concept rather than a validated clinical test. The IGTP team plans to expand longitudinal studies in broader sporadic Parkinson’s cohorts to determine whether platelet RNA signatures can help track cognitive decline or assess responses to disease-modifying treatments.
Sources: Neuroscience News.