title: Effect of the methylenetetrahydrofolate reductase (MTHFR 677C>T) polymorphism on plasma homocysteine concentrations in healthy children is influenced by consumption of folate-fortified foods.
abstract: OBJECTIVE
  To explore the influence of folate-fortified foods (ready-to-eat [RTE] breakfast cereals or fruit-juice drinks) on the relation between the methylenetetrahydrofolate reductase (MTHFR 677C>T) polymorphism and plasma total homocysteine (tHcy) concentrations in healthy children.
  
  
  METHODS
  This was a cross-sectional study by face-to-face interview. A total of 186 sixth-grade students participated from randomly selected primary schools in Volos, Greece. Fasting plasma tHcy, folate, and vitamin B12 were measured. The MTHFR genotypes were determined. Anthropometric data were collected and dietary intake was assessed by two non-consecutive 24-h recalls. Participants were characterized as non-consumers of RTE breakfast cereals or fruit-juice drinks if there was no report of any such food during the 24-h recall interviews; all other children were classified as consumers.
  
  
  RESULTS
  Geometric means for plasma tHcy were higher, whereas plasma folate was lower in non-consumers compared with consumers. The sample was divided by consumption status (yes or no) to explore the significance of each polymorphism depending on consumption status. The association between the genotype and tHcy was restricted to non-consumers (P<0.05). Specifically, only in children who did not consume RTE breakfast cereals or fruit-juice drinks did the TT genotype carriers exhibit higher tHcy concentrations when compared with C-allele carriers (P<0.05). In contrast, in consumers, circulating tHcy was similar regardless of genotype.
  
  
  CONCLUSIONS
  These observational findings support a beneficial effect of RTE breakfast cereals and fruit-juice drinks on lowering plasma tHcy and improving folate status in children. Also, consumption of folate-fortified foods modulates the association of the MTHFR 677C>T polymorphism with tHcy, suggesting that habitual consumption of folate-fortified foods is a practical approach in providing consistent protection to those children who may benefit the most, i.e., carriers of the TT genotype.
authors.affiliation: Laboratory of Nutrition and Clinical Dietetics, Department of Nutrition and Dietetics, Harokopio University, Athens, Greece. tina.papoutsakis@hua.gr
authors.forename: Constantina
authors.initials: C
authors.lastname: Papoutsakis
authors.forename: Yannis
authors.initials: Y
authors.lastname: Manios
authors.forename: Faidon
authors.initials: F
authors.lastname: Magkos
authors.forename: Evaggelos
authors.initials: E
authors.lastname: Papaconstantinou
authors.forename: Kleopatra H
authors.initials: KH
authors.lastname: Schulpis
authors.forename: Antonis
authors.initials: A
authors.lastname: Zampelas
authors.forename: Antonia L
authors.initials: AL
authors.lastname: Matalas
authors.forename: Nikos
authors.initials: N
authors.lastname: Yiannakouris
mesh_terms: D001628:Beverages; D002648:Child; D003430:Cross-Sectional Studies; D004032:Diet; D002523:Edible Grain; D005260:Female; D005492:Folic Acid / Q000008:administration & dosage / Q000097:blood / Q000235:genetics*; D005527:Food, Fortified; D005638:Fruit; D005838:Genotype; D006115:Greece; D006710:Homocysteine / Q000097:blood / Q000235:genetics*; D006801:Humans; D008297:Male; D042965:Methylenetetrahydrofolate Reductase (NADPH2) / Q000235:genetics*; D011110:Polymorphism, Genetic; D014803:Vitamin B Complex / Q000008:administration & dosage / Q000097:blood / Q000235:genetics*
chemical_list: D006710:Homocysteine; D014803:Vitamin B Complex; D005492:Folic Acid; D042965:Methylenetetrahydrofolate Reductase (NADPH2)