SNCA and synucleinopathy: This result is in line with the report that synucleinopathy strains exist in a back-to-back paired filament structure of the α-synuclein fibrilization core, including PD strains (Guerrero-Ferreira et al., 2018; Li et al., 2018) and MSA strains type I and II (Schweighauser et al., 2020).