SNCA and Parkinson disease: Autopsy studies of PD patients with RBD have revealed significant α-synuclein deposits in the subcortical and brainstem nuclei, suggesting that the pathogenesis of RBD may involve regions such as the ventral-lateral gray matter around the aqueduct, the lateral pontine tegmentum, and the nucleus of the pontine pedunculi (Lu et al., 2006; Luppi et al., 2011).