The maternal immune activation model of psychosis leads to decreased IL-10 levels at both the maternal fluids and in the foetal brain, causing a set of psychotic-like behaviour disturbances, which are all prevented by IL-10 overexpression in the macrophages of pregnant dams (Smith et al., 2007; Oskvig et al., 2012; Meyer, 2014). The gene discussed is IL10; the disease is psychotic disorder.