Abnormal accumulation and fibril formation of SNCA lead to the appearance of Lewy bodies and neurites in the PD brain as one of its histopathological hallmarks, whereas LRRK2 is a multifaceted protein with as yet ill-defined functions in the brain whose mutant variants are the second most common genetic risk factor for iPD (Benson and Huntley, 2019; Panicker et al., 2021; Vázquez-Vélez and Zoghbi, 2021). Here, LRRK2 is linked to Parkinson disease.