What is more, the genes expression of MAPK, ELAVL1, RAB14, KLF9, ARF1, ARFGAP1, ATG7, ABCA7, SFT2D2, E2F2, MAPK7, and UHRF1 were both significantly decreased in PD (Figure 6(b)). The gene discussed is KLF9; the disease is Parkinson disease.