However, it was not known exactly why folic acid was able to so radically reduce birth defects, or why the supplement did not eliminate neural tube birth defects in all pregnancies. However, researchers at the University of Texas in Austin have discovered that a mutation in an enzyme of folic acid can produce birth defects in mice.
The research has revealed that one of the ways that folic acid prevents birth defects is by ensuring the production of a metabolite called formate in the developing embryo. Embryos require formate or they do not develop correctly. This goes a long way to explaining why 30 percent of neural tube birth defects cannot be prevented with folic acid supplements.
While the tests were carried out on mice, they have given researchers a strong model system that they can use to give a better understanding of folic acid and its role in birth defects in people. Humans actually share the exact same gene for the folic acid enzyme as mice, and as such the research has gone a long way to improve the wellbeing of human babies.
Scientists are now looking for nutrients and minerals that could be given to pregnant women. These have the potential to completely eliminate all of the neural tube birth defects that cannot be prevented with the folic acid supplement. In time it should be possible to screen women during pregnancy to ascertain whether they are deficient in the enzyme. At that point it would be easy to treat the problem, and make birth defects far less likely.