IFNG and Parkinson disease: However, accumulating evidence shows that Parkinson’s disease is accompanied by immune responses that lead to an increase in serum levels of pro-inflammatory cytokines such as interleukin-6 (IL6), tumor necrosis factor alpha (TNFα), interleukin-1β (IL1B), and interferon gamma (IFNG) (Brodacki et al., 2008; Koziorowski et al., 2012; Lindqvist et al., 2012; Dzamko et al., 2015; Houser and Tansey, 2017; Caggiu et al., 2019).