This is a project assessing mitochondrial function in patients with neurodegenerative disease (Parkinsons, corticobasal degeneration, multiple systems atrophy, progressive supranuclear palsy and essential tremor) compared to controls. The material is blood cells. Functional mitochondrial analyses have been performed, measuring oxygen consumption in blood cells. About 160 subjects in total. NGS targeted on mtDNA using TWIST capture has been performed on an Illumina platform. Two research questions: 1) Is there a difference in occurrence of mtDNA deletions and general mutation load between controls and the difference disease groups? 2) More explorative, as preliminary data for future larger studies: What variants in mtDNA are associated with high or low mitochondrial respiratory function in the material in total.