In 1997, when evidence of the link between α-synuclein and PD was officially recognized, Stanley Prusiner was awarded the Nobel Prize for his pioneering work on prion disease, in which he presented the revolutionary theory according to which prions are “infectious agents able to replicate and propagate in the host in the absence of nucleic acids and endowed of strain specific properties” [11,12]. The gene discussed is SNCA; the disease is Parkinson disease.