BST1 and Parkinson disease: We identified a set of genes and molecular pathways that are specific for GBA-related PD, such as a deregulation of SNCA and pathways related to metabolism of beta-amyloid and aging compared to PD, as well as dysregulation of the lysosomal, membrane trafficking, and mitochondrial processing in manifesting compared to non-manifesting GBA-carriers (including genes such as LRRK2, ATP13A2, BST1 and NOTCH1), also confirmed at the ultrastructural level in monocytes.