TGFB1 and schizophrenia: In this study, we aimed to investigate the association between following polymorphisms: IL2 −330T>G (rs2069756), IL6 −174G>C (rs1800795), INFG +874T>A (rs2430561) in the Polish population and for the first time to investigate the role of selected TGFB1 polymorphisms—TGF-β1 +869T>C (rs1800470) and TGF-β1 +913G>C (rs1800471) in susceptibility to schizophrenia.