Moderate elevation of plasma total homocysteine (tHcy) is a strong and independent risk factor for coronary artery disease (CAD).
It can result from genetic or nutrient-related disturbances in the transsulfuration or remethylation pathways for Hcy metabolism.
A point mutation (C677T ; Ala-to-Val) in the gene encoding the 5,10-methylenetetrahydrofolate reductase (MTHFR) has been recently reported to render the enzyme thermolabile and less active.
Studies on the role of this mutation as a risk factor for CAD have given conflicting results.
We studied a total of 415 subjects, 278 with angiographically documented multivessel CAD and 137 with angiographically documented normal coronary arteries.
The overall frequency of the MTHFR VN homozygous genotype was 15.7% (with 52.5% heterozygous and 31.8% normal).
Subgroup analysis showed no significant differences between CAD and CAD-free subjects.
A genotype/phenotype correlation study showed a marked effect of folate on the association between MTHFR genotypes and tHcy.
Among individuals with folate levels below the median (11.5 nmol/L), fasting tHcy was significantly increased not only in VN homozygotes (by 59%) but also, at intermediate values, In AN heterozygotes (by 21% on average).
Conversely, the mutation resulted neutral with respect to tHcy levels In subjects with adequate folate levels.
We conclude that, In our population, the MTHFR C677T mutation is rather common, but it does not appear to be associated per se to CAD. (...)
Mots-clés Pascal : Cardiopathie coronaire, Athérosclérose, Plasma sanguin, Folate, Homocystéine, Methylenetetrahydrofolate reductase (NADPH), Oxidoreductases, Enzyme, Mutation, Gène, Italie, Europe, Facteur risque, Epidémiologie, Homme, Appareil circulatoire pathologie, Aminoacide, Génétique
Mots-clés Pascal anglais : Coronary heart disease, Atherosclerosis, Blood plasma, Folate, Methylenetetrahydrofolate reductase (NADPH), Oxidoreductases, Enzyme, Mutation, Gene, Italy, Europe, Risk factor, Epidemiology, Human, Cardiovascular disease, Aminoacid, Genetics
Notice produite par :
Inist-CNRS - Institut de l'Information Scientifique et Technique
Cote : 98-0308701
Code Inist : 002B12A03. Création : 27/11/1998.