SNCA and Parkinson disease: Moreover, point mutations (A53T, A30P, E46K, G51D, and several others) and multiplications (duplications or triplications) of the SNCA gene (coding for α-synuclein) have been reported in individuals with familial PD with autosomal dominance (Polymeropoulos et al., 1997; Krüger et al., 1998; Zarranz et al., 2004; Klein and Westenberger, 2012; Kiely et al., 2013).