In another line, multiple missense point mutations (such as A30P, G51D, E46K, A53T, and A30P) of the α-synuclein coding gene have been identified in the familial PD cases from different populations including Spanish, Italian-American, and German [22–26], which aggravate the misfolding and aggregation of this protein in the SNpc of patients. This evidence concerns the gene SNCA and Parkinson disease.