GBA1 and Parkinson disease: PD is the second most common CNS disease, which is pathologically characterized by the loss of dopaminergic neurons in the substantia nigra and the appearance of the protein aggregates, named Lewy bodies, in the midbrain.[109] To date, Multiple GWAS have identified more than 90 genetic variants contributing to disease risk and progression for early‐onset and later‐onset PD, including rare and common genetic variants, such as SNCA, GBA, LRRK2, VPS13C, and PRKN.