Of 22 genes (ATP13A2, ATXN3, CHCHD2, DNAJC13, FBXO7, GAK, GBA, GCH1, LRRK2, MAPT, PARK7, PINK1, POLG, PRKN, RAB29, RAB39B, SCARB2, SNCA, SREBF1, STX1B, SYNJ1, and VPS35)25 involved in mutations and pathogenesis in familial and idiopathic PD, the expression of CHCHD2 had a 2.28-fold increase in patients with PD (p = 3.02 × 10−5, FDR = 0.00417) in the first cohort (Supplementary Fig. S4). This evidence concerns the gene POLG and Parkinson disease.