Mutations or polymorphisms in the gene of the enzyme methylenetetrahydrofolate reductase (MTHFR), as C677T, A1298C and G1793A, are associated with hyperhomocysteinemia and possibly with elevated risk for vascular diseases.
The prevalences of the C677T and A1298C genotypes did not differ significantly in 772 individuals with documented coronary artery disease (CAD), 137 individuals with deep-vein thrombosis (DVT), and 329 individuals without documented vascular disease.
Further studies are needed to establish whether the C677T and the A1298C mutations have an impact on vascular disease in the Ashkenazi Jewish population.
Two common polymorphisms (677C>T and 1298A>C) in the gene coding for MTHFR have been shown to reduce MTHFR enzyme activity and were associated with the susceptibility to different disorders, including vascular disease, neural tube defects and lymphoid malignancies.