CHCHD2 and Parkinson disease: Consistent with the results obtained by immunofluorescence in Fig. 2e–h, the number of CHCHD2 positive cells (Fig. 3a, p < 0.0001, Mann–Whitney U test) and density of CHCHD2 in the surviving cells (Fig. 3b, p < 0.01, Mann–Whitney U test) of substantia nigra of PD patients were reduced significantly, compared with control.