Fairfoul and colleagues demonstrated α-synuclein seeding activity using a small number of CSF samples, and positive reactions were observed in 11/12 autopsy-confirmed cases of pure DLB (92% sensitivity), 11/17 cases of DLB with Alzheimer’s disease (65% sensitivity), 2/13 cases of Alzheimer’s disease with incidental Lewy bodies, and 2/2 cases of PD (100% sensitivity) [237]. Here, SNCA is linked to early-onset autosomal dominant Alzheimer disease.