Additionally, since alterations in bile acids (BAs) have been previously noted in PD , , , a target study of BAs in serum was performed. Finally, a cell study in isogenic neurons generated from a PD+/LRRK2+ patient was conducted to investigate the potential neurotoxic effects of a chemical found in the household dust, using various readouts related to mitochondrial function. To our knowledge, this is the first study investigating the environmental influences of LRRK2 penetrance through the molecular analysis of household dust.