The serum level of IL-12 in patients with AD is increased as distinct from patients with PD [59,61] and, vice versa, the registered level of IL-2 and C-reactive protein in the blood of PD patients is higher compared to healthy donors, whereas in AD these cytokines are not significantly changed [22,59,60,62,65,72]. The gene discussed is IL2; the disease is Parkinson disease.