A much-reduced expression of MTHFR (p < 0.01) and an abnormally high expression of methionine synthase reductase (p < 0.001) were observed in the NTD group.
For rs1801394 within MTRR, children carrying allele G and genotype GG had a higher NTDs risk (OR=1.533, 95%CI=1.102~2.188; OR=2.355, 95%CI=1.044~5.312, respectively).
The present meta-analysis indicated that MTRRA66G polymorphism, but not MTR A2756G, is significantly associated with maternal risk for NTDs in Caucasians.
Meta-analyses were conducted to set the results of the case-control study in the context of eligible literature on the relation between the MTRR 66A>G variant and NTD risk.
We studied the MTRR polymorphisms I22M (66A-->G), S175L (524C-->T), and K350R (1049A-->G) as potential NTD risk factors in a large homogeneous Irish NTD population.
Maternal-fetal interaction was also detected when offspring carried the MTHFR 677C-->T variant and mothers carried the MTRR 66A-->G variant, resulting in a significantly elevated risk of NTD.
According to the results of this study, the genetic predisposition to NTD can be correlated with the 677TT genotype in the MTHFR gene, 677CT/1298AC haplotype (the MTHFR gene), 2756G allele in the MTR gene, 66AG variant and minisatellite sequence with 5 or 10 repeats in intron 6 of the MTRR gene.
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.
MTRR, combined with a low level of vitamin B12, increases the risk of NTD and of having a child with NTD in Canada, while TCN 776 GG and MTRR 66 GG mutated genotypes associated with the MTHFR 677 CC wild-type are predictors of NTD cases in Sicily.