Specifically, knockdown of Stmn2 upregulated nine PD GWAS genes (GPNMB, SREBF1, STAB1, LHFPL2, PRRG4, CTSB, FNDC3B, PPFIBP1, and COL5A2), and downregulated one PD GWAS gene (SYT4) at the mRNA level. Here, CTSB is linked to Parkinson disease.