Abstract: ObjectiveTo explore the relationship between plasma homocysteine (Hcy), polymorphism in 5,10-methylenetetrahydrofolate reductase (MTHFR) and cystathionine-β-synthase (CBS), and cerebral thrombosis.Methods87 subjects with first-ever acute cerebral thrombosis and 80 controls were studied. The plasma Hcy levels were measured using high-performance liquid chromatography-fluorescence detection (HPLC-FD). The polymorphism in MTHFR was determined by a polymerase chain reaction (PCR) assay and subsequent restriction enzyme digestion and that in CBS was determined by amplification refractory mutation system (ARMS).ResultsThe fast plasma Hcy level in the patient group was (15.28±4.33)μmol/L significantly higher than that ( 11.32 ±3.86)μmol/L in the control group (P<0.001). Different genotype had different influence on the plasma Hcy levels. There were no differences in genotype frequencies or allele frequencies between the patient group and control group (P>0.05).ConclusionCommon mutations in MTHFR, CBS G919A and CBS T833C lead to hyperhomocysteinemia. Hyperhomocysteinemia, but not common mutations in MTHFR and CBS is associated with the increased incidence of cerebral thrombosis.

Key words: homocysteine, 10-methylenetetrahydrofolate reductase, cystathionine-β-synthase, polymorphism, cerebral thrombosis