SNCA and Parkinson disease: In an initial candidate gene study, we studied the blood expression of all PARK genes, of the previously reported PD blood biomarker ST13 and of promising transcripts that encode putative SNCA-interactor proteins (Fig. 2A,B) and showed altered levels in our previous global transcriptome profiling of midbrain tissue in a carefully characterized synucleinopathy mouse model with dopaminergic deficits, impaired synaptic plasticity and mitochondrial dysfunction (Kurz et al., 2010; Platt et al., 2012; Tozzi et al., 2012; Gispert et al., 2015a,b; Subramaniam et al., 2014; Brehm et al., 2015b).