Background: Hyperhomocysteinemia has been associated with venous thrombosis. Under known and unknown conditions the C677T mutation in the 5,10-methylenetetrahydrofolate reductase (MTHFR) gene is accompanied by elevated levels of homocysteine. However, the relationship of this mutation with venous thromboembolism (VTE) remains controversial. The purpose of this study was to evaluate the association of the MTHFR mutation with VTE.
Methods: The presence of the C677T mutation in the MTHFR gene was investigated in a population of 176 consecutive patients with a history of venous thromboembolism and in a control group of 300 healthy subjects, using DNA analysis.
Results: The prevalence of homozygosity in the patient group was 13.6% and in healthy subjects 10%. The odds ratio for venous thromboembolism in the presence of the homozygous genotype (677TT) was 1.4 (95% confidence interval (C.I.), 0.8 to 2.5), which was not statistically significant.
Conclusions: Homozygosity for the T677 allele of the MTHFR gene, although slightly more prevalent in patients compared to controls, has not been found in association with venous thromboembolism.