How high-risk pregnancies affect neurological development disorders
A recent study reports on the role of the maternal placenta as a previously unknown link between the genes and the development of possible neurological development disorders such as schizophrenia, ADHD, autism, dyslexia and Tourette syndrome. According to the researchers involved in the study, there is a strong link between complications during pregnancy, certain genetic preconditions and the development of mental illnesses. This connection is apparently controlled via the placenta.
Based on the research results, it will be possible in future to predict more precisely who is at risk of mental illness. The work also enables new therapeutic approaches to reduce or even prevent mental illness. The placenta, which has so far been completely neglected, plays a central role in this. The study was carried out by researchers from the "Lieber Institute for Brain Development" (LIBD) in Baltimore and was recently published in the journal "Nature Medicine".
The placenta has always been very important in mythology
In old customs and also in many primitive peoples, the placenta is said to have healing or good luck effects. For example, it was processed in the form of powder or as an essence into medicinal products or buried in the garden and a tree planted on it. Homeopathy also uses the placenta as a remedy. From a scientific point of view, the mother cake has played a minor role so far, but the latest research results could change that.
Early complications in pregnancy
“For the first time, we have found an explanation for the connection between early complications, genetic risk and their effects on mental illnesses,” explains LIBD director Daniel R. Weinberger in a press release on the study results. It was revealed that the placenta makes a central contribution to this development. In previous studies on this subject, only certain genetic preconditions were considered to be a risk of mental illness.
What role does the placenta play?
The placenta supplies the embryo with nutrients and chemicals that are essential for normal prenatal development. The scientists found that many genes associated with the risk of schizophrenia appear to indirectly change early brain development by affecting the placenta. These genes become active when there are complications during pregnancy.
Schizophrenia and the womb
For more than 25 years, researchers have assumed that the risk of a neurological development disorder such as schizophrenia develops during pregnancy and shortly after birth. So far, scientists have assumed that genetic variants alone are responsible for this development. However, the biological mechanisms were poorly understood. The most recent study shows that the combination of pregnancy complications and certain genetic variants increases the risk of certain neurological development disorders by at least five times.
Course of the study
The researchers in Baltimore examined over 2,800 adults, 2038 of whom had schizophrenia. The subjects were of different ethnic origins and came from different continents, including North America, Europe and Asia. All have been subjected to genetic testing. The birth history of the participants was also considered. The researchers found a strong interaction between pregnancy complications and genes that are associated with a risk of schizophrenia.
Pregnancy complications and genetic preconditions
The researchers showed that people with a high genetic risk who had severe complications during pregnancy were at least five times more likely to develop schizophrenia compared to people with a similarly high genetic risk but who did not Pregnancy complications occurred. In experiments, the scientists found that the genes responsible for schizophrenia are active during the complications and, as a result, the placenta becomes increasingly stressed and shows, for example, more inflammatory reactions.
Placenta as the new heart of research
The mother's permanent stress affects the baby through the amniotic fluid. This was already shown by a Zurich research group in 2017. "The surprising results of this study make the placenta the heart of a new area of biological research in connection with the interaction of genes and the environment," summarizes Weinberger. In future studies, new approaches for therapeutic treatments and prevention strategies will be tested, in which the placenta plays a central role. (vb)