SNCA and Alzheimer disease: Furthermore, a recent study reported detection of α-synuclein RT-QuIC seeding in 3/6 nasal brushing samples and 6/6 CSF samples from mixed DLB/AD (meeting diagnostic criteria for dementia with Lewy bodies but with positive AD biomarkers in CSF), the first time concomitant α-synuclein pathology has been identified by α-synuclein RT-QuIC of nasal brushings (Perra et al., 2021).