Parents' genes influence the amount of care and attention that a mother will give to her child

Without a doubt, pregnancy is a life-changing event. Women are undergoing great physiological and psychological changes, including a veritable swarm of hormones that prepares them for the overwhelming task of motherhood.

In this sense, a study conducted by scientists from the University of Cardiff in the United Kingdom suggests that the father's genes are not only a model for the growth of their offspring, but they can also have the ability to influence the level of attention that the mother will provide to her son, even before she is born.

they claim that paternal genes carried by a fetus can affect the maternal brain during pregnancy, preparing the mother to spend more or less time looking after her children.

The research team investigated the role of the placenta, which transports nutrients to the growing fetus and emits hormonal signals into the mother's bloodstream to establish and maintain a successful pregnancy.

In addition to participating in the development of the baby during pregnancy, placental signals are considered important for programming the mother's behavior, preparing her for her new role.

These hormones are produced by placental cells called spongiotrophoblasts, whose proliferation is kept under control by a gene called Phlda2. However, there is a peculiarity: the developing fetus has two copies of the Phlda2 gene, but unlike most genes, only one copy of Phlda2 is active

This is due to an intriguing evolutionary phenomenon called genomic imprint, by which only the copy of the gene from one of the parents is on. In the case of Phlda2, it is the father's copy silenced

Using genetically modified mice, the researchers observed what happened if both copies of the fetal gene Phlda2 were active or inactive

. the researchers found that mothers exposed to puppies with the highest activity of Phlda2 (both active copies of the gene) cared for and cherished their puppies less and focused on nest building.

On the contrary, mothers exposed to the lowest dose of Phlda2 (both copies of the inactive gene), they spent more time feeding their puppies and doing fewer household chores. The authors also showed changes in two regions of the mother's brain: the hypothalamus and the hippocampus.

The results were clear: differences in fetal gene expression during pregnancy were sufficient to rewire the mother's brain.

The authors assume that these results may be relevant to humans, since levels of Phlda2 gene activity vary between human pregnancies and are inversely correlated with placental hormones. , which is of critical importance to the well-being of the unborn baby

Reference: Maternal care stimulated by the paternal print in mammals. Plos Biology, 2018. https://doi.org/10.1371/journal.pbio.2006599