Beyond the role of MC-I in mitochondrial dysfunction, mutations in PINK1, the gene encoding for PTEN-induced putative kinase 1 (PINK1), are associated with mitochondrial dysfunction in PD, whereas patients who are heterozygous for mutations in PINK1 present with reduced intensity on 18F-fluoro-levodopa PET compared with controls [135]. Here, PINK1 is linked to Parkinson disease.