Notably, MAPT and SNCA have synergistic effects in the pathogenesis of PD (Goris et al., 2007; Clarimón et al., 2009; Williams-Gray et al., 2009; Setó-Salvia et al., 2011; Morley et al., 2012; Nombela et al., 2014; Winder-Rhodes et al., 2015; Paul et al., 2016). The gene discussed is SNCA; the disease is Parkinson disease.