C4B, Complement C4-A (C4A), Complement C2 (C2), A2M, LRG1, and the Fibrinogen alpha, beta, and gamma chains (FGA, FGB, and FGG) were differentially expressed between those who transitioned to psychosis and those who did not, adjusting for age, sex, and study. The gene discussed is FGB; the disease is psychotic disorder.