(From EurekAlert). A number of research groups have published recently on the relationship between age-related mitochondrial DNA damage and Parkinson's disease. Here is another: research "shows that oxygen free radicals are damaging proteins in mitochondria, the tiny cellular 'batteries' of brain cells. This damage may be one main cause of Parkinson's Disease (PD), the chronic movement disorder that affects at least one million Americans. [Scientists] believe the damage is taking place in a large protein structure called complex I, the first stop in the electron transport chain, which produces an electrical charge inside mitochondria. Mitochondria then use this electrical charge to make energy. ... complex I assembly in Parkinson's had 50 percent more damage from oxygen, [showed] evidence of not being properly assembled and had reduced electron flow." A good thing that methods of replacing damaged mitochondrial DNA are within sight.