SNCA and Parkinson disease: Based on the fact that synucleinopathy is a common pathological characteristic of PD (Courte et al., 2020; Stoyka et al., 2020), we decided to use the single-cell transcriptomic database Dropviz.org (Saunders et al., 2018) to explore the relationship between the cellular localization of Snca and GWAS-implicated genes (Figure 3).