The reduction of ALDH1A1 expression may contribute to the etiopathogenesis of PD (Galter et al., 2003; Mandel et al., 2007; Werner et al., 2008; Grunblatt et al., 2017), whereas an increase of ALDH1A1 levels protects against dopaminergic neurodegeneration (Cai et al., 2014; Liu et al., 2014). This evidence concerns the gene ALDH1A1 and Parkinson disease.