Cerebrospinal fluid and postmortem brains of PD patients also displayed elevated levels of the proinflammatory cytokines like tumor necrosis factor- (TNF) α, interleukin- (IL-) 1β and IL-6 (McCoy et al., 2006 ▶; Ferrari et al., 2006 ▶; Rocha et al., 2015 ▶). The gene discussed is IL6; the disease is Parkinson disease.