SPHK1 and Parkinson disease: The top 40 genes included TLR9; GPNMB; PTEN-induced kinase 1 (PINK1), a well-established familial PD gene55; Unc-51 like autophagy activating kinase 1 (ULK1), the initiating enzyme in autophagy56; and sphingosine kinase 1 (SPHK1), nicotinamide phosphoribosyltransferase (NAMPT), and sirtuin 1 (SIRT1), which impact neurodegeneration and aging processes57,58.