The aim of this study was to investigate the association ofthe rs823144 single nucleotide polymorphism (SNP), locatedin the promoter region of RAB29, with PD risk, RAB29 geneexpression, lysosomal hydrolase activity – including glucocerebrosidase(GCase), α-galactosidase (GLA), galactocerebrosidase(GALC), and acid sphingomyelinase (ASMase) –and the concentrations of lysosphingolipids in the blood. The gene discussed is SMPD1; the disease is Parkinson disease.