SNCA and Parkinson disease: Pathological deposits of misfolded α-synuclein are often accompanied by posttranslational modifications of α-synuclein, such as increased phosphorylation, in particular at Ser129, which has frequently been used to characterize the extent of neuropathology in the brains of PD patients and in animal models of synucleinopathies (9, 16, 31).