LRRK2 and Parkinson disease: Approximately 10% of inherited PD patientsand 2% of sporadic cases carry LRRK2 mutations (e.g., G2019S, I2020T,R1441C), suggesting LRRK2 mutation likely as a common etiology underlyingboth inherited and sporadic PD.6−9 Notwithstanding growing evidence supporting the deeplinkage of LRRK2 dysfunction with both inherited and non-inheritedPD, it is still challenging to elucidate the physiological and/orpathological role of LRRK2 due to its complexity.