Furthermore, miRNA-133 also has been linked to the pathogenesis of PD and, knowing that the miR-133-pituitary homeobox 3 (Pitx3) feedback loop plays a critical role in maintaining the dopaminergic neurons in the brain, the slightest deregulation in miRNA-133 levels might promote PD’s onset. This evidence concerns the gene PITX3 and Parkinson disease.