LRRK2 and Parkinson disease: Altered lysosomal function because of altered LRRK2 kinase activity can also be observed in carriers of mutant LRRK2; independently of PD status, they show an increase in the lysosomal lipid bis(monoacylglycero)phosphate (BMP) in urine, which is reversed by LRRK2 kinase inhibition (Jennings et al., 2022; Merchant et al., 2023).