Omega 3 in pregnancy: fatty acid transmission to the fetus depends on mom's genes

The amounts of Omega 3 that reach the fetus in gestation depend on both the mother's and the baby's genes. This was announced by Eva Lattka, a researcher at the Helmholtz Zentrum in Munich, Germany, during the 11th European Conference on Nutrition in Madrid, Spain. According to the results obtained by Lattka and colleagues, the genes involved encode fatty acid desaturase (FADS), enzymes involved in the synthesis of omega-3 and omega-6 fatty acids. These same genes would determine how these nutrients are processed during gestation.

Omega-3 from mom to baby

The variants of FADS genes that can be present in a cell are different. Previous studies have shown that the type of gene carried by the mother influences the proportion of different fatty acids in the woman's blood. In particular, some variants are less active and their presence changes the fatty acid content of the maternal blood. Although during gestation the fetus takes up Omega-3s necessary for its development from the placenta through the umbilical cord, no previous research has unraveled how FADS genes affect the presence of these molecules in the umbilical cord itself. The association between variant FADS genes and levels of DHA (docosahexaenoic acid), an Omega-3 that is important for the development of the child's nervous system, has also not been fully elucidated. For this reason, Lattka and her staff decided to analyze the relationship between FADS genes and the amounts of fatty acids in umbilical cord plasma. The researcher explained that the latter is an index of fatty acid supply to the fetus during gestation.

Mother and child, the outcome depends on both

The study involved analyzing the presence of 17 known FADS gene variants in more than 4,000 pregnant women and their children. The levels of fatty acids present in mothers-to-be were determined by analyzing their red blood cells after the 20th week of gestation. Finally, the association between the presence of the different genetic variants and the amounts of Omega-6 and Omega-3 present at the time of birth in the umbilical cord of more than 2,000 babies was evaluated. The statistical analysis, conducted by Colin Steer of the University of Bristol (UK), showed that the amount of DHA present in the red blood cells of pregnant women depends on the variant of the FADS genes present. Not only that, the data obtained indicate that the type of genes present in the mother can influence the supply of DHA to the baby during gestation. Lattka pointed out that this effect is independent of the type of nutrition followed by the mother. However, the analyses revealed that the amounts of fatty acids present in the umbilical cord depend on both maternal and baby genes. In fact, while the genes present in the mother determine the fatty acid precursor that will be transferred to the child, it will be the latter's genes that will enable the production of a particular fatty acid. The researchers therefore concluded that DHA levels depend on both the mother's and the fetus' metabolism.