GBA1 and Parkinson disease: Here, we have developed a system to investigate RNA-level changes that are linked to 11 of the 20 most common familial PD hereditary genes, including PRKN, SNCA, LRRK2, PINK1, DNAJC6, FBXO7, SYNJ1, DJ1, VPS13C, ATP13A2 and GBA1 (Poewe et al. 2017).