SynthesisEuropean journal of nutrition2017
The impact of MTHFR 677 C/T genotypes on folate status markers: a meta-analysis of folic acid intervention studies.
Synthesis in European journal of nutrition, 2017. The graph could read no effect estimate from its abstract, so it casts no vote on the map. Cited by 28 papers, 1 of them a synthesis that pooled it.
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The trial behind it
Trials whose registry record cites this paper, or whose number appears in the abstract. A trial that started after this paper was published is citing it as background, not reporting it.
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Who cites it
28 citing papers in PubMed, 1 synthesis or guideline pooled it, 57 citations in OpenAlex.
- Association Study between Polymorphisms in DNA Methylation-Related Genes and Testicular Germ Cell Tumor Risk.Cancer epidemiology, biomarkers & prevention : a publication of the American Association for Cancer Research, cosponsored by the American Society of Preventive Oncology · 2022Pooled it
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- Food Intervention with Folate Reduces TNF-α and Interleukin Levels in Overweight and Obese Women with theNutrients · 2020Trial
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- Budd-Chiari Syndrome: Presentation, Management, and Prognosis.The American journal of gastroenterology · 2026Review
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- Precision Medicine in Astronauts: Principles and Targets in Molecular Assessment.Methods in molecular biology (Clifton, N.J.) · 2026Review
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- Folic Acid and Methyltetrahydrofolate Supplementation in theNutrients · 2024Article
- Factors Influencing Collateral Circulation Formation After Indirect Revascularization for Moyamoya Disease: a Narrative Review.Translational stroke research · 2024Review
- Genetic variants of MTHFR gene in relation to folic acid levels and bone mineral density in Polish patients with inflammatory bowel disease.Journal of applied genetics · 2024Article
- Relationship between homocysteine, vitamin B9, vitamin B12 levels methylenetetrahydrofolate reductase (C677T, A1298C) polymorphisms, and cryptogenic stroke in Tunisian adults´ patients: a case-control study.The Pan African medical journal · 2024Article
- Surgical outcomes following encephaloduroarteriosynangiosis in moyamoya disease associated with hyperhomocysteinemia.Brain and behavior · 2023Article
- Infants' Folate Markers and Postnatal Growth in the First 4 Months of Life in Relation to Breastmilk and Maternal Plasma Folate.Nutrients · 2023Article
- Individualized folic acid supplementation based on MTHFR and MTRR gene polymorphisms reduces the risk of gestational diabetes mellitus in a Chinese population.International journal of clinical and experimental pathology · 2023Article
- Need for a nutrition-specific scientific paradigm for research quality improvement.BMJ nutrition, prevention & health · 2023Review
- One size does not fit all: on the need for categorical stratification in nutrition science, practice and policy.BMJ nutrition, prevention & health · 2023Article
- Article
Corrections and comments
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Authors and funding
5 authors at 2 institutions in 1 country.
Funding
No grant is acknowledged in the PubMed record.
Abstract
purposeMethylenetetrahydrofolate reductase (MTHFR) is a key folate pathway enzyme with the T variant of the MTHFR gene increasing the risk of low folate status, particularly coupled with low folate intake. As genetic variability of MTHFR influences folate status, it is important to ensure an adequate intake that overrides genetic effects but minimises any adverse effects. Our aim was to assess the influence of MTHFR genotype on folate status followed by response to supplementation.
methodsWe performed a meta-analysis of ten folate intervention studies to assess the degree to which MTHFR C677T genotype influenced plasma homocysteine and serum folate levels as measures of folate status. We then examined response after supplementation at intake values up to the upper tolerable limit.
resultsThe MTHFR 677TT genotype was associated with higher plasma homocysteine (2.7 μmol/L, TT vs. CT/CC; 2.8 μmol/L, TT vs. CC) and lower serum folate (2.5 nmol/L, TT vs. CT/CC; 3.6 nmol/L, TT vs. CC). In two studies, the TT groups had mean plasma Hcy >15 μmol/L. Serum folate levels were >7 nmol/L for all genotype groups. After supplementation of 400 up to 1670 μg DFEs of folic acid or folic acid + fortified foods and/or natural food folates for a minimum of 4 weeks, there were no significant differences in plasma homocysteine levels; however, individuals with the TT genotype had a lower serum folate response to supplementation (7.2 nmol/L, TT vs. CT/CC; 8.7 nmol/L, TT vs. CC).
conclusionsThis meta-analysis confirms observations from observational and intervention studies that MTHFR TT genotype is associated with increased plasma homocysteine and lowered serum folate and less response to short-term supplementation. The results can be used for modelling and guiding personalised intake recommendations for the nutrient folate.
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