We also found significant enrichment of the genes in many pathways, including signaling by VEGF, axon guidance, signaling by FGFR, Interleukin-2 signaling, PI3K/AKT activation, negative regulation of PI3K/AKT network, and RAF/MAP kinase cascade, among others, in the PD-OS regulatory network (FDR < 0.05) (Figure 6b). Here, AKT1 is linked to Parkinson disease.