Folate Status Response to Controlled Folate Intake Is Affected by the Methylenetetrahydrofolate Reductase 677C→T Polymorphism in Young Women

• Published in: The Journal of nutrition Vol. 133; no. 12; pp. 4107 - 4111
• Main Authors: Shelnutt, Karla P., Kauwell, Gail P.A., Chapman, Carrie M., Gregory, Jesse F., Maneval, David R., Browdy, Angeleah A., Bailey, Lynn B., Theriaque, Douglas W.
• Format: Journal Article
• Language: English
• Published: Bethesda, MD Elsevier Inc 01.12.2003; American Society for Nutritional Sciences
• Subjects: 5,10-Methylenetetrahydrofolate Reductase (FADH2) - genetics; 5′10-methylenetetrahydrofolate reductase; Adequate Intakes; Adult; age; bioavailability; Biological and medical sciences; blood serum; Cytosine; Dietary Reference Intakes; Dose-Response Relationship, Drug; enzyme activity; erythrocytes; Erythrocytes - metabolism; experimental diets; Feeding. Feeding behavior; Female; folate; folic acid; Folic Acid - administration & dosage; Folic Acid - blood; Fundamental and applied biological sciences. Psychology; genotype; homocysteine; Homocysteine - blood; Humans; metabolic studies; methylenetetrahydrofolate reductase; nationalities and ethnic groups; nutrition-genotype interaction; nutritional intervention; nutritional status; polymorphism; Polymorphism, Genetic - genetics; repletion; Thymine; Vertebrates: anatomy and physiology, studies on body, several organs or systems; vitamin deficiencies; vitamin metabolism; women; young adults; young women; young women; folate; DFE; LS; MTHFR; DRI; 5′10-methylenetetrahydrofolate reductase; RDA; genotype; NTD; Human; Nutrition; Enzyme; Genotype; Folic acid; Folate; Micronutrient; Female; Oxidoreductases; 5'10-methylenetetrahydrofolate reductase; Polymorphism; Reductase
• ISSN: 0022-3166; 1541-6100
• DOI: 10.1093/jn/133.12.4107

This study was designed to evaluate the effect of the methylenetetrahydrofolate reductase (MTHFR) 677C→T polymorphism on folate and homocysteine response in nonHispanic women consuming a low folate diet followed by a diet providing the Recommended Dietary Allowance (RDA) for folate. Women (aged 20–30 y old) with either the TT (n = 19) or CC (n = 22) MTHFR 677C→T genotype participated in a folate depletion-repletion study (7 wk, 115 μg dietary folate equivalents (DFE)/d; 7 wk, 400 μg DFE/d). Overall serum folate decreased (P < 0.0001) during depletion and increased (P < 0.0001) during repletion with lower (P = 0.03) postdepletion serum folate in women with the TT versus CC genotype. Folate status was low (serum folate < 13.6 nmol/L) in more women with the TT (59%) compared with the CC genotype (15%) postdepletion. Red blood cell folate for all subjects decreased during depletion (P < 0.0001) and repletion (P = 0.02) with lower (P = 0.04) red blood cell folate in women with the TT compared with the CC genotype postrepletion. Homocysteine increased (P < 0.0001) for both genotype groups postdepletion and decreased (P = 0.02) postrepletion for the CC genotype group only. Homocysteine concentrations tended to be higher (P = 0.09) in the TT versus CC genotype group postdepletion and postrepletion. These data suggest that the MTHFR 677C→T polymorphism negatively affects the folate and homocysteine response in women consuming low folate diets followed by repletion with the RDA. These results may be important when evaluating the impact of the MTHFR 677C→T polymorphism in countries in which low folate diets are chronically consumed.