In the last two decades, several studies have reported that MTHFR polymorphisms, particularly 677C>T and 1298A>C, are associated with an increased risk for neural tube defects [38], cardiovascular diseases [39], schizophrenia [40], neoplasia [41,42,43], and hyperhomocysteinemia [44]. This evidence concerns the gene MTHFR and isolated spina bifida.