Like BPA, folic acid can affect the coat color of mice. This is shown by earlier studies by the research team. In another series of experiments, the researchers now both BPA and folic acid in the feed. The result: The vitamin was able to counteract the effects of BPA, so that the mice were born neither too many yellow nor too many brown animals. Genistein, an ingredient of soybean, had a similar effect.
Although the yellow mice look different than their brown spotted siblings, they show no difference in the sequence of their DNA building blocks. Rather, there are significantly more so-called methyl groups on the DNA strand of brown spotted mice. These chemical switch molecules block a gene responsible for the yellow coat color and thus affect the appearance of mouse children? a form of inheritance called epigenetics. BPA decreases the number of chemical switches and folic acid increases it again, which is reflected in the opposite effect of the two substances on the coat color.
However, the results of the animal experiments can not be readily transferred to humans. So researchers can not yet tell what amounts of BPA in human embryos lead to epigenetic change. The same applies to the optimal dose of folic acid or genistein. Randy Jirtle, one of the researchers, warns that excessive levels of genistein could also be harmful. displayDana Dolinoy (Duke University in Durham) et al .: PNAS, online pre-publication, DOI: 10.1073_pnas.0703739104 ddp / science.de? Larissa Kessner