Peripheral levels of Interleukin-1β (IL-1β), Interleukin-6 (IL-6), and tumor necrosis factor-α (TNF-α) are elevated during first-episode psychosis and psychotic relapses in schizophrenia [54,55], as well as in the pathogenesis [56] and complications of type 2 diabetes [57,58]. This evidence concerns the gene TNF and schizophrenia.