Several of the 36 DEGs, including KCNJ6, ACOX1, USP9X, SMAD2, SLC8A1, PIK3C3, PDK1, have been previously reported to be implicated in the pathogenesis of PD (Rott et al., 2011; di Val Cervo et al., 2017; Muñoz et al., 2020). Here, SMAD2 is linked to Parkinson disease.