UBE2K and Parkinson disease: To correlate these findings with genes previously identified as differentially expressed in PD post-mortem brains and blood [29, 30], we have found a significant difference of expression in the very same “Validation set” for Aldehyde Dehydrogenase 1 Family, member A (ALDH1A1) (P = 1.51E-02), Proteasome (prosome, macropain) 26 S subunit PSMC4 (P = 1.80E-03) and Heat shock 70 kDa protein 8 (HSPA8) (P = 8.20E-03) but not for Huntingtin interacting protein 2/ubiquitin-conjugating enzyme E2K (HIP2/UBE2K) (P = 3.00E-04) (Fig. 2b).