House finches experience an influx of local and systemic pro-inflammatory cytokine production (IL-1β, IFN-γ, TNF-α) early in infection with MG (Adelman et al., 2013; Vinkler et al., 2018), and individual variation in conjunctivitis is significantly predicted by individual variation in local IL-1β expression. Here, IFNG is linked to conjunctivitis.