SIRT2 could differentiate PD from APS with good sensitivity and specificity (AUC = 0.713; 95% CI: 0.61–0.81; cut-off: 15.35 ng/μL; Figure 1D) as well as APS from GC (AUC = 0.787; 95% CI: 0.68–0.89; cut-off: 13.07 ng/μL; Figure 1E). The gene discussed is SIRT2; the disease is Parkinson disease.