Genetic Polymorphism of 5,10-Methylenetetrahydrofolate Reductase (MTHFR) as a Risk Factor for Coronary Artery Disease

Abstract
Background Epidemiological studies have identified hyperhomocyst(e)inemia as an independent risk factor for coronary artery disease (CAD). Recently, the alanine/valine (A/V) polymorphism of the 5,10-methylenetetrahydrofolate reductase (MTHFR) gene, one of the key enzymes catalyzing remethylation of homocysteine, has been reported. The VV genotype correlates with increased plasma homocyst(e)ine levels as a result of the reduced activity and increased thermolability of this enzyme. In this study, we examined the distribution of the MTHFR genotypes in Japanese men and the association between the VV genotype and CAD. Methods and Results The diagnoses of CAD of all the studied patients were confirmed by coronary angiography. The MTHFR genotype was analyzed by PCR followed by HinfI digestion. In 778 healthy male subjects, the frequency of the V allele was 0.33, comparable to that in a French Canadian population. In 362 patients with CAD, the VV genotype was significantly more frequent than in control subjects (...