For example, increased copy number of APP for Alzheimer’s (Wisniewski et al., 1985; Mann and Esiri, 1989) and of alpha-synuclein SNCA for Parkinson’s disease (Singleton et al., 2003; Chartier-Harlin et al., 2004; Ibáñez et al., 2004). Here, SNCA is linked to Parkinson disease.