Fig. 5: Workflow for MRI processing and imaging transcriptomics analysis.

a T1-weighted images from MSA patients and HCs were processed to derive cortical thickness, volume, and deformation metrics. Scan harmonization corrected inter-scanner variability, and regional values were converted to W-scores. For subsequent analyses, average W-scores across MSA patients were used for each brain region. b Regional gene expression values were extracted from postmortem brain data. Using PLS, the MSA brain atrophy vector was linked with gene expression, followed by gene set enrichment analysis to identify significant terms in MSA-relevant regions. HC healthy control, MSA multiple system atrophy, PLS Partial least squares regression, SD standard deviation, T1-w T1-weighted.