NPC1 and Lewy body dementia: Natural variants in NPC1 are not associated with increased risk of PD (Ouled Amar Bencheikh et al. 2020; Zech et al. 2013); however, some of the substrates that accumulate in Niemann–Pick Type C1, such as cholesterol, have been identified as dysregulated in idiopathic PD (Huang et al. 2019; Park et al. 2021) and DLB (Bettcher et al. 2017; Bosco et al. 2006).