SNCA and Parkinson disease: Intracerebral injection of brain extracts from all cases of MSA and most cases of PD, as well as injection of assembled recombinant human α-synuclein, into heterozygous M83 mice resulted in staining for pS129-α-synuclein and motor dysfunction, leading to hindlimb paralysis (Figs. 1, 4 and 5).