The α-synuclein gene (SNCA) was the first gene definitely associated with familiar PD, and there are three known missense point mutations, A53T and A30P and E46 K, besides duplication and triplication of SNCA, that all lead to an early disease onset (Polymeropoulos et al. 1997; Kruger et al. 1998; Singleton et al. 2003; Chartier-Harlin et al. 2004). Here, SNCA is linked to Parkinson disease.