IFNG and psychotic disorder: Despite numerous studies, findings regarding serum IFN-γ levels in SCZ remain inconsistent – some reports indicate elevated levels [62,104] (FES and ultra-high risk (UHR) for psychosis patients [105]), increased IFN-γ mRNA expression [106], and higher IFN-γ concentrations in cerebrospinal fluid (CSF) [107], while others suggest decreases [108,109,110], and still others show no significant differences compared to controls [43,59,111,112,113], depending on disease phase and methodological differences.