These findings suggest that the dopaminergic pathways in circulating lymphocytes have relevant immunomodulatory functions in the pathology of MS, impacting the development of drugs for patients with MS—DR agonists have beneficial effects as an add-on to immunomodulatory treatments with such agents as IFN-β, and they might act preferentially on D1-like rather than D2-like receptors [238]. This evidence concerns the gene IFNB1 and myeloid sarcoma.