When using ADP-ribosyl cyclase (coded by BST1) as exposure and PD as outcome, the primary outcome of IVW model showed that an increased level of ADP-ribosyl cyclase was causally associated with the higher risk of PD (OR[95%CI] = 1.08 [1.01, 1.16], p =0.02) (Figure 3A). This evidence concerns the gene BST1 and Parkinson disease.