Furthermore, the result of the meta-analysis supported the association between MTRR 66A>G and NTDs risk (G allele vs. A allele: OR = 1.32, 95% CI = 1.09-1.61, GG + GA vs. AA: OR = 1.49, 95% CI = 1.06-2.09, GG vs. AA: OR = 1.61, 95% CI = 1.04-2.49).Our study confirmed that the MTRR 66A>G and MTR 2756A>G were significantly associated with the increased NTDs risk in a Chinese population.
5-Methyltetrahydrofolate-homocysteine methyltransferase (MTHM) 501A>G in case of GDM, and betaine-homocysteine methyltransferase (BHMT) 716G>A in case of no folate supplementation significantly associated with NTDs (both P<.05), whereas the two genotypes alone did not significantly associate with NTDs (both P>.05).
The aim of the current study was to investigate maternal MTHFR and MS polymorphisms and the interaction between them and their influence on children with NTDs in the Shanxi Province of northern China.
The present meta-analysis indicated that MTRR A66G polymorphism, but not MTRA2756G, is significantly associated with maternal risk for NTDs in Caucasians.
No significant NTD association was found with S175L or K350R in cases or their parents and no interactions were observed between these polymorphisms and the D919G variant of MTR or the A222V variant of 5,10-methylenetetrahydrofolate reductase (MTHFR).
Results of screening mutations 2756A-->G and 66A-->G in MTR and MTRR genes respectively show that are might have an effect on NTDs incidence among the examined population.
We evaluated the association of polymorphisms of three genes affecting vitamin B12-dependent remethylation of homocysteine, transcobalamin (TC), methionine synthase (MTR) and MTR reductase (MTRR), combined or not with methylenetetrahydrofolate reductase (MTHFR), with the risk of having neural tube defect in 40 children with spina bifida and 58 matched controls from South Italy.
When broken down into the various 677 ct MTHFR and 2756ag MetSyn genotypes, carriage of the 677ct MTHFR allele appears to affect formyl-H(4)PteGlu metabolism in non-NTD mothers.
Genetic polymorphisms in methylenetetrahydrofolate reductase and methionine synthase, folate levels in red blood cells, and risk of neural tube defects.
The observation that homocysteine and vitamin B(12) levels are independent predictors of NTD risk suggested that methionine synthase could be a candidate gene for NTDs.
Using a Midwestern NTD population consisting of probands, parents, and siblings from Iowa, Minnesota, and Nebraska, we analyzed a range of candidate genes, including 5,10-methylenetetrahydrofolate reductase (MTHFR), folate receptors-alpha (FOLR1; hereafter abbreviated "FR-alpha") and -beta (FOLR2; hereafter, "FR-beta"), methionine synthase (hereinafter, "MS"), T, the human homolog of the murine Brachyury gene, and the paired-box homeotic gene 3 (PAX3), for association with NTDs.
This study, though limited, provides no evidence for a major involvement of MS in the aetiology of homocysteine-related diseases such as NTD or vascular disease.
We discuss the possibility that a mild deficiency of methionine synthase activity could be associated with mild hyperhomocysteinemia, a risk factor for cardiovascular disease and possibly neural tube defects.
In addition, they suggest directly that mutations in methionine synthase can lead to elevated homocysteine, implicated both in neural tube defects and in cardiovascular diseases.