In a large comparative cohort of patients with Parkinson’s disease (PD), frontotemporal dementia (FTD) and progressive supranuclear palsy (PSP), Zech et al. reported identified only a single pathogenic NPC1/NPC2 variants in six patients (1.1%), which did not differ significantly from the frequency of heterozygous variants in the general population [36]. Here, NPC2 is linked to Parkinson disease.