Korean Journal of Biological Psychiatry

Objectives：Recently in schizophrenia high incidence of MTHFR(methylenetetrahydrofolate reductase), which is a main relating enzyme that reduce homocysteine level, genetic variations were reported. So we examined serum homocysteine level and MTHFR gene polymorphism in Korean schizophrenics.

Method：We compared serum homocysteine level and MTHFR polymorphism between 235 schizophrenics (100male, 135female) and 235 normal controls(100male, 135female). C677T and A1298C polymorphism of MTHFR gene were analyzed. 

Results：1) C677T genetic mutation(CT and TT) were more frequent in schizophrenia group than normal control group(p<0.01). But the difference of A1298C mutation frequency was not found between two groups. 2) In schizophrenia patients, TT genotype of C677T mutation showed significantly higher homocysteine level (29.99uM/L) than other group(CT：13.34uM/L, CC：9.34uM/L p<0.01). 3) MTHFR 677 TT homogeneous mutation genotype showed two times more risk(odds ratio=2.15) than 677CC normal genotype in schizophrenia.

Conclusion：Some schizophrenia patients with high homocysteine serum level may have C677T TT genotype. In that case, folate ingestion could be a good management for clinical improvement.

Keywords Schizophrenia;Homocysteine;MTHFR;Polymorphism.