The first published mutation identified A53T substitution in α-syn resulting from an autosomal-dominant single base pair change in SNCA. Following this discovery, further autosomal dominant mutations in the SNCA gene have been found to cause familial PD including E46K, H50Q, G51D, A53T, A53E, A53V and A30P (Flagmeier et al., 2016). Here, SNCA is linked to Parkinson disease.