Cultured fibroblasts of a 47-year-old woman affected by a multisystem disorder characterized by progressive, early-onset parkinsonism and other impairments associated with a novel homozygous mutation in DJ-1 showed lowered ATP synthesis, high ROS levels, and reduced subunits of complex I, and abnormal markers of oxidative stress in the blood [104]. Here, PARK7 is linked to Parkinson disease.