Some of hub genes shown in Figures 4B,C have been reported in previous studies of PD: Krt25 is implicated in motor coordination (Zhang et al., 2018); Aqp1, encoding astrocytic water channel proteins aquaporin 1 (AQP1) might profoundly affect α-syn deposition in the neocortex of patients with PD (Hoshi et al., 2017); FolR1 is selectively expressed in the surface of midbrain DA progenitors and its level may represent the condition of TH positive neurons (Gennet et al., 2016). Here, AQP1 is linked to Parkinson disease.