They included 99 studies with 8,234 participants and found that peripheral levels of the following cytokines differed between patients with schizophrenia and healthy controls in more than 50% of the included studies, listed according to falling prevalence among the studies: IL-6, TNF-α, IL-10, IFN-γ, IL-1β, IL-8, IL-2, IL-1RA, furthermore the gene polymorphisms for TNF-α 1800629, IL-6 rs1800795, and IL-1β rs16944, and elevated expression levels of IL-6, TNFR1, TNFR2, and IL-1β mRNAs (3). The gene discussed is IL2; the disease is schizophrenia.