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The schizophrenia and Toxoplasma gondii connection: Infectious, immune or both?



Recent research has suggested a possible link between toxoplasmic agents and schizophrenia. We aimed to assess this by measuring Toxoplasma gondii-associated antibodies in schizophrenia patients and controls


We used a commercially available enzyme-linked immunosorbent assay (ELISA) kit to measure the level of immunoglobulin G (IgG) and IgM antibodies in serum samples from schizophrenia patients (n=40) and from a group of non-schizophrenic control subjects (n=37)


Among schizophrenic patients, 16 (40%) showed IgG seropositivity and two (5%) showed IgM seropositivity. Among the control group, five (13.5%) were found have IgG seropositivity and one (2.7%) showed IgM seropositivity. In our study we found that IgG T gondii antibodies were significantly higher in schizophrenia patients compared with controls


This study supports the theory that toxoplasmic agents may have a role in the aetiology of schizophrenia

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Correspondence to Gulden Sonmez Tamer.

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Tamer, G.S., Dundar, D., Yalug, I. et al. The schizophrenia and Toxoplasma gondii connection: Infectious, immune or both?. Adv Therapy 25, 703–709 (2008).

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  • enzyme immunoassay
  • schizophrenia
  • Toxoplasma gondii