ArticleJournal of epidemiology2008
Serum folate and methylenetetrahydrofolate reductase (MTHFR) C677T polymorphism adjusted for folate intake.
Article in Journal of epidemiology, 2008. The graph could read no effect estimate from its abstract, so it casts no vote on the map. Cited by 18 papers, 2 of them syntheses that pooled it.
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The trial behind it
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Who cites it
18 citing papers in PubMed, 2 syntheses or guidelines pooled it, 43 citations in OpenAlex.
- Associations between C677T and A1298C polymorphisms of MTHFR and susceptibility to rheumatoid arthritis: a systematic review and meta-analysis.Rheumatology international · 2017Pooled it
- MTHFR gene polymorphisms and outcome of methotrexate treatment in patients with rheumatoid arthritis: analysis of key polymorphisms and meta-analysis of C677T and A1298C polymorphisms.The pharmacogenomics journal · 2013Pooled it
- Coevolution of Human Diet and Gut Microbiome: Implications for Nutrigenomics and Cross-Population Health.International journal of microbiology · 2026Review
- The Interrelationship between Preconception Folate Nutritional Intake and Child Genetic Liability in the Risk of Childhood Acute Lymphoblastic Leukemia.Cancer epidemiology, biomarkers & prevention : a publication of the American Association for Cancer Research, cosponsored by the American Society of Preventive Oncology · 2025Article
- MTHFR Gene Polymorphisms: A Single Gene with Wide-Ranging Clinical Implications-A Review.Genes · 2025Review
- Impaired folate status in patients with mental disorders.Acta neuropsychiatrica · 2025Article
- The Implication of a Polymorphism in the Methylenetetrahydrofolate Reductase Gene in Homocysteine Metabolism and Related Civilisation Diseases.International journal of molecular sciences · 2023Review
- Cerebral venous thrombosis with hyperhomocysteinemia due to loss of heterozygosity at methylenetetrahydrofolate reductase (MTHFR) locus: a case report.BMC neurology · 2023Article
- Effects of Folic Acid Supplementation on Liver Enzymes, Lipid Profile, and Insulin Resistance in Patients with Non-Alcoholic Fatty Liver Disease: A Randomized Controlled Trial.Advanced biomedical research · 2023Article
- Methylenetetrahydrofolate Reductase C677T Gene Variant in Relation to Body Mass Index and Folate Concentration in a Polish Population.Biomedicines · 2022Article
- Article
- A case-control analysis of maternal diet and risk of neural tube defects in Bangladesh.Birth defects research · 2019Article
- Heterogeneity in Metabolic Responses to Dietary Fructose.Frontiers in genetics · 2019Review
- Determinants of folate and vitamin B12 plasma levels in the French E3N-EPIC cohort.European journal of nutrition · 2018Article
- Preventive medical services not covered by public health insurance at Daiko Medical Center in Japan, 2004-2011.Nagoya journal of medical science · 2012Article
- Serum folate and homocysteine and depressive symptoms among Japanese men and women.European journal of clinical nutrition · 2010Article
- Folate concentrations in pediatric patients with newly diagnosed inflammatory bowel disease.The American journal of clinical nutrition · 2009Article
- Study of C677T Methylene Tetrahydrofolate Reductase Gene Polymorphism as a Risk Factor for Neural Tube Defects.Asian journal of neurosurgeryArticle
Corrections and comments
PubMed lists nothing against this paper. Absence here is not a guarantee, only a check that was made.
Authors and funding
9 authors at 2 institutions in 1 country.
Funding
No grant is acknowledged in the PubMed record.
Abstract
backgroundSerum folate concentration is lower in individuals with the methylenetetrahydrofolate reductase (MTHFR) 677TT genotype than in those with the MTHFR 677CC or 677CT genotypes. Since studies considering folate intake are limited, we examined the association between folate intake and serum folate levels, according to the genotype.
methodsThe subjects comprised 170 Japanese persons (74 males and 96 females) aged 20-75 years who visited a clinic to test for Helicobacter pylori infection. Folate intake was estimated using a semiquantitative food frequency questionnaire, and serum folate was measured in the residual fasting blood samples of the subjects. MTHFR C677T was genotyped using polymerase chain reaction.
resultsThe geometric means of serum folate level were 6.19, 6.20, and 5.17 ng/mL among the 60 participants with the 677CC genotype, 90 participants with the 677CT genotype, and 20 participants with the 677TT genotype, respectively. No difference was noted in the mean folate intake estimated using the food-frequency questionnaire. Regression analysis showed that log(e)(serum folate) adjusted for age, sex, and log(e)(folate intake) was significantly lower among those with the 677TT genotype than among those with the 677CT or 677CC genotypes (p = 0.01). The adjusted reduction in serum folate was 20.2% (95% confidence interval, 5.4-32.6%) in the case of the 677TT genotype relative to the levels in the case of the 677CC/677CT genotypes. When folate intake was adjusted for total energy intake, using the residual method, the slope of the regression line for 677TT was smaller than those of the regression lines for 677CC and 677CT.
conclusionIndividuals with the 677TT genotype may need to consume more folate to maintain serum folate levels similar to those found in individuals with the 677CC/677CT genotypes.
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Read under generation 80e0d062 · epoch 390. Bibliography from PubMed, PubMed Central and OpenAlex; grants from NIH RePORTER; trial links from ClinicalTrials.gov; estimates, votes and beliefs from the OpenQuestion graph.