Effect of Diet and 677 C®T 5, 10-Methylenetetrahydrofolate Reductase Genotypes on Plasma Homocyst(e)ine Concentrations in Slovak Adolescent Population

K. RAŠLOVÁ, A. BEDEROVÁ¹, J. GAŠPAROVIČ, P. BLAŽÍČEK², B. SMOLKOVÁ

Received January 13, 2000
Accepted March 17, 2000

Summary
The objective of this study was to evaluate the effect of diet and 677 C®T mutation of the methylenetetrahydrofolate reductase (MTHFR) gene on plasma homocyst(e)ine concentrations in an adolescent population (113 males, age: 14.2±2.4 years; 202 females, age: 14.9±2.1 years) from a region characterized by high cardiovascular mortality. Homocyst(e)ine levels did not differ between males and females (9.4±3.5 and 8.9±3.1 mmol/l, respectively). The homozygosity for the 677 C®T MTHFR mutation was found in 4.6 % of subjects. No differences in homocyst(e)ine levels were found between MTHFR genotypes. Analysis of the diet composition which was performed on a 24-hour daily recall basis and a food frequency questionnaire showed a low daily intake of vitamin B6 (males: 1.13 mg/66 % RDA; females: 0.92 mg/61 % RDA). Daily folic acid intake was 0.21 g/105 % RDA in males and 0.23 g/115 % RDA in females. The results of our study show that the high homocyst(e)ine levels in the adolescent population were not affected by the 677 C®T MTHFR mutation. We conclude that an insufficient dietary intake of vitamin B6 and folic acid is responsible for this finding. This is in accord with the recommendation that the dietary allowances for folate should be reset to the originally prescribed levels of 0.4 g/day which should be sufficient to control the homocysteine levels.

Key words
Homocysteine · 677 C®T methylenetetrahydrofolate reductase genotypes · Diet · Vitamin B6 · Folic acid

Reprint requests
K. Rašlová, Department of Lipid and Glucose Metabolism, Institute of Preventive and Clinical Medicine, Limbová 14, 833 01 Bratislava, Slovak Republic. Tel/Fax: +421 7 59369161, e-mail: raslova@upkm.sk