Antioxidant compounds inhibit the formation of and destabilize preformed α-synuclein fibrils in vitro (Ono and Yamada 2006) and have some protective effects in models of PD (Trinh et al. 2008; Beal 2011; Martin et al. 2012; Martinez-Banaclocha 2012). This evidence concerns the gene SNCA and Parkinson disease.