CTSB and Parkinson disease: In context of PD, SNPs located in 3′UTR of FGF20, SNCA, PARKIN, LRRK2, CTSB, STX1B, IGSF9B, and HSD3B7 have been reported to be associated with Parkinson's disease through impact of their miRNA-binding strength and miRNA-mediated regulation of themselves [36–41].