These include the PD loci of PARK1-15, such as SNCA, Parkin, Dj-1, and LRRK2, and other PD-associated genes, such as MAPT, GBA, SMPD1, and LRP10 (Nalls et al., 2019; Bandres-Ciga et al., 2020; Day and Mullin, 2021; Song et al., 2022). Here, SMPD1 is linked to Parkinson disease.