To explore whether there is reduced pS65-parkin in the SN of sporadic PD patient brains, we examined 2 normal human brains (C1 and C2) and 2 PD brains (PD-1 and PD-2) that did not carry PINK1 or PARK2 mutations, but displayed ubiquitinated aggregates (Figure 7B) and Lewy bodies (Supplemental Figure 9B) in the SN. Here, PRKN is linked to Parkinson disease.