RRM2 and Parkinson disease: As the gap analysis results from the external dataset GSE20141, the expression of ASGR2, FGF10, FGF19, HJURP, NTF3, RRM2, SLC22A1, SLC28A3 and WNT1 genes were significantly increased in PD samples, whereas the genes CCNA1, OIP5, and WNT10B were significantly decreased (Figure 8A).