SNCA and Parkinson disease: These DANs show some of the most common features of PD such as α-synuclein (SNCA) aggregates, overexpression of oxidative stress genes, lower number of neurites, caspase-3 activation (Nguyen et al., 2011; Sánchez-Danés et al., 2012), and upregulation of PGC-1a (Seibler et al., 2011).