We examined separate and interaction effects of psychosis liability and childhood trauma on serum levels of BDNF, CCL-2, CRP, IFN-γ, IGFBP2, IL-6, PDGF, SCF and TNF-α in 40 patients with recent onset psychosis, 13 patients at Ultra-High Risk (UHR) for psychosis, 31 unaffected siblings of psychosis patients and 41 healthy controls. This evidence concerns the gene CCL2 and psychotic disorder.