Our findings revealed that PPBP levels in the peripheral blood samples of patients with PD and healthy controls were 1.770 μg/mL (range 0.019–9.839 μg/mL) and 2.269 μg/mL (range 0.692–16.83 μg/mL) respectively (Figure 9A). This evidence concerns the gene PPBP and Parkinson disease.