Recently, some groups have applied the Protein Misfolded Cyclic Amplification (PMCA) or Real-Time Quaking-Induced Conversion (RT-QuIC) assays, which were established initially for the detection of abnormal prion protein in Creutzfeldt-Jakob disease, to the amplification of misfolded α-synuclein aggregates from brain lysates or CSF samples of patients with PD. Here, SNCA is linked to Parkinson disease.