Neural tube defects (NTD) are complex embryological malformations with multifactorial inheritance. Their prevalence in Italian population is five in 10000 births. Periconceptional folate intake reduces their occurence risk by 70%, but the protective mechanism remains unknown. A common SNP, the C677T mutation, in the methylenetetrahydrofolate reductase (MTHFR) gene, a key enzyme in the folic pathway, is the first identified genetic risk factor for NTDs. The C677T polymorphism was associated with a 2-4-fold increased risk if the NTD affected child or the mother are homozygous for this mutation. Recently, a second common polymorphism in the MTHFR gene, the A1298C mutation, has been identified. Combined heterozygosity for both the C677T and A1298C mutation might be another genetic risk factor for NTD and account for a proportion of folate-related NTD. Finally, a polymorphism in the MTRR (Methionine Synthase Reductase) gene, an A66G substitution, increases NTDs risk when cobalamin status is low. So, this polymorphism provides the first reported genetic link between vitamin B12 deficiency and NTDs. Recent studies have demonstrated that both gene-gene interactions and gene-environment interactions can play a role in NTD pathogenesis. Efforts are currently underway to study in the Italian population the frequency of these common SNPs and their possible role as risk factors. Infact, the identification of the major risk factors in Italian population will allow to identify women at risk for bearing a child with NTDs and could result in a better compliance of women that want to become pregnant to take folate periconceptionally.
|Translated title of the contribution||Folate pathway single nucleotide polymorphisms (SNPs) and neural tube defects|
|Number of pages||7|
|Publication status||Published - 2001|
ASJC Scopus subject areas
- Pediatrics, Perinatology, and Child Health