LRRK2 and Parkinson disease: Consistent with previous findings of elevated mtDNA mutations in G2019S LRRK2 non-PD-manifesting carriers [117], we observed an increase in mtDNA in G2019S LRRK2 non-manifesting carriers as well, establishing an increase in mtDNA damage is associated with pathogenic LRRK2, irrespective of PD diagnosis.