SMPD1 and Parkinson disease: A total of 6 variants in ATP13A2 (p.Gly217Ser, p.Arg745His; and c.2762+21T>C), GIGYF2 (p.Arg1225Cys), and SMPD1 (p.Val147Val and p.Arg378Cys), were found as putatively contributing to PD (Table 2).