Homocysteine concentrations in adults with trisomy 21: effect of B vitamins and genetic polymorphisms

• Published in: The American journal of clinical nutrition 2004-12, Vol.80 (6), p.1551-1557
• Main Authors: Fillon-Emery, N, Chango, A, Mircher, C, Barbe, F, Blehaut, H, Herbeth, B, Rosenblatt, D.S, Rethore, M.O, Lambert, D, Nicolas, J.P
• Format: Article
• Language: English
• Subjects: 5-Methyltetrahydrofolate-Homocysteine S-Methyltransferase - genetics; Administration, Oral; Adolescent; Adult; Adults; Biological and medical sciences; blood chemistry; Case-Control Studies; Chromosome aberrations; cystathionine beta-synthase; Cystathionine beta-Synthase - genetics; Dietary Supplements; Down syndrome; Down Syndrome - blood; Down Syndrome - drug therapy; Down Syndrome - genetics; Drug Synergism; Female; Ferredoxin-NADP Reductase - genetics; folic acid; Folic Acid - administration & dosage; Folic Acid - blood; Genes; genetic polymorphism; Genotype; homocysteine; Homocysteine - blood; Homocysteine - drug effects; Homozygote; Humans; Male; Medical disorders; Medical genetics; Medical sciences; Membrane Transport Proteins - genetics; methionine synthase; methionine synthase reductase; methylenetetrahydrofolate reductase; Methylenetetrahydrofolate Reductase (NADPH2) - genetics; Middle Aged; mutation; Polymorphism; Polymorphism, Genetic; pyridoxine; Reduced Folate Carrier Protein; trisomics; Vitamin B; Vitamin B 12 - administration & dosage; Vitamin B 12 - blood; Vitamin B 6 - administration & dosage; vitamin B12
• ISSN: 0002-9165; 1938-3207
• DOI: 10.1093/ajcn/80.6.1551

Background: The effects of supplementation with B vitamins and of common polymorphisms in genes involved in homocysteine metabolism on plasma total homocysteine (tHcy) concentrations in trisomy 21 are unknown. Objectives: We aimed to determine the effects of orally administered folic acid and of folic acid combined with vitamin B-12, vitamin B-6, or both on tHcy in adults with trisomy 21. The study was also intended to analyze the possible influence of gene polymorphisms. Design: One hundred sixty adults with trisomy 21 and 160 healthy, unrelated subjects aged 26 +/- 4 y were included. Plasma tHcy, red blood cell folate, serum folate, and vitamin B-12 were measured. Genotyping for the common methylenetetrahydrofolate reductase (MTHFR) 677C leads to T, MTHFR 1298A leads to C, cystathionine beta-synthase 844Ins68, methionine synthase 2756A leads to C, methionine synthase reductase 66A leads to G, and reduced folate carrier 80G leads to A polymorphisms was carried out. Results: The mean tHcy concentration (9.8 +/- 0.7 micromol/L) of cases who did not use vitamins was not significantly different from that of controls (9.4 +/- 0.3 micromol/L). Plasma tHcy concentrations (7.6 +/- 0.3 mmol/L) in cases who used folic acid were significantly lower than in cases who did not. Folic acid combined with vitamin B-12 did not significantly change tHcy concentrations compared with those in cases who used only folic acid. Folic acid combined with vitamins B-6 and B-12 significantly lowered tHcy (6.5 +/- 0.5 micromol/L). The difference in tHcy according to MTHFR genotype was not significant. However, tHcy concentrations were slightly higher in TT homozygotes among the controls but not among the cases. Conclusion: This study provides information on the relation between several polymorphisms in genes involved in homocysteine and folate metabolism in adults with trisomy 21.