Other biomarkers (APOE, NTRK2, SLCO1B3, SLC28A3, AQP10, SNCAIP, ANO2, CADM1, PTPRD, GPR32, GPR321, SQOR, SULT1C2, GABRG2, CYP4Z1, CDH13, and FANCF) were also related to the clinical characteristics of PD (e.g., cognition, motor, age at onset, etc.). Here, NTRK2 is linked to Parkinson disease.