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. 2019 Oct 11;16(10):e1002931. doi: 10.1371/journal.pmed.1002931

Fig 1. Overview of study.

Fig 1

We used SOMAScan 1.1k (left panel) and 1.3k (right panel) assays to quantify plasma protein levels in the Discovery and Replication Cohorts, respectively. Multiple linear regression models revealed 140 proteins that differed in PD versus NC individuals in the Discovery Cohort (p < 0.005). Stability Selection with LASSO was then used to rank the 140 candidate proteins from the Discovery Cohort, obtaining the top 10 most robust and stable proteins. Four (ACY1, BSP, GHR, OMD) of these 10 proteins differed in PD versus NC samples in the Discovery Cohort and also differentiated PD versus NC in the Replication Cohort (middle panel, 1). These were tested for specificity for PD (2), influence of dopaminergic medication or sample handling (3, 4), and ability to predict subsequent rates of cognitive decline (5). ACY1, aminoacylase-1; ALS, amyotrophic lateral sclerosis; BSP, bone sialoprotein; GHR, growth hormone receptor; LASSO, least absolute shrinkage and selection operator; MCI, mild cognitive impairment; NC, neurologically normal control; OMD, osteomodulin; PD, Parkinson’s disease; PDBP, Parkinson’s Disease Biomarker Program.