[The study of the association between the C677T polymorphism of the methylenetetrahydrofolate reductase gene and severity of symptoms in patients with schizophrenia].

Objective: To study the association of the C677T polymorphism of the methylenetetrahydrofolate reductase (MTHFR) gene with the risk of schizophrenia in a large sample, including schizophrenic patients and mentally healthy people, and to investigate the relationship of this polymorphism with the severity of schizophrenia symptoms and genotype-environment interaction effects on these symptoms.

Material And Methods: The sample for genotyping consisted of 1357 patients with schizophrenia and schizophrenia spectrum disorders and 711 people of the control group. The severity of symptoms was assessed with the PANSS. Obstetrical complications and a traumatic brain injury in medical history were studied as environmental factors.

Results And Conclusion: No association was found between C677T polymorphism and schizophrenia. There was no genotype effect on the severity of symptoms on the PANSS subscales. The effect of genotype-environment interactions on the severity of schizophrenia symptoms was not detected. The results do not confirm the data of a number of studies on the relationship of C677T polymorphism with schizophrenia symptoms.