Skip to main content

High levels of estrogen in the womb linked to autism

Scientist have identified a link between exposure to high levels of oestrogen sex hormones in the womb and the likelihood of developing autism. The findings are published today in the journal Molecular Psychiatry.
Autism/puzzle brain abstract concept
The discovery adds further evidence to support the prenatal sex steroid theory of autism first proposed 20 years ago.
In 2015, a team of scientists at the University of Cambridge and the State Serum Institute in Denmark measured the levels of four prenatal steroid hormones, including two known as androgens, in the amniotic fluid in the womb and discovered that they were higher in male foetuses who later developed autism. These androgens are produced in higher quantities in male than in female foetuses on average, so might also explain why autism occurs more often in boys. They are also known to masculinise parts of the brain, and to have effects on the number of connections between brain cells.
Today, the same scientists have built on their previous findings by testing the amniotic fluid samples from the same 98 individuals sampled from the Danish Biobank, which has collected amniotic samples from over 100,000 pregnancies, but this time looking at another set of prenatal sex steroid hormones called oestrogens. This is an important next step because some of the hormones previously studied are directly converted into oestrogens.
All four oestrogens were significantly elevated, on average, in the 98 foetuses who later developed autism, compared to the 177 foetuses who did not. High levels of prenatal oestrogens were even more predictive of likelihood of autism than were high levels of prenatal androgens (such as testosterone). Contrary to popular belief that associates oestrogens with feminisation, prenatal oestrogens have effects on brain growth and also masculinise the brain in many mammals.
Professor Simon Baron-Cohen, Director of the Autism Research Centre at the University of Cambridge, who led this study and who first proposed the prenatal sex steroid theory of autism, said: "This new finding supports the idea that increased prenatal sex steroid hormones are one of the potential causes for the condition. Genetics is well established as another, and these hormones likely interact with genetic factors to affect the developing foetal brain."
Alex Tsompanidis, a PhD student in Cambridge who worked on the study, said: "These elevated hormones could be coming from the mother, the baby or the placenta. Our next step should be to study all these possible sources and how they interact during pregnancy."
Dr Alexa Pohl, part of the Cambridge team, said: "This finding is exciting because the role of oestrogens in autism has hardly been studied, and we hope that we can learn more about how they contribute to foetal brain development in further experiments. We still need to see whether the same result holds true in autistic females."
However, the team cautioned that these findings cannot and should not be used to screen for autism. "We are interested in understanding autism, not preventing it," added Professor Baron-Cohen.
Dr Arieh Cohen, the biochemist on the team, based at the State Serum Institute in Copenhagen, said: "This is a terrific example of how a unique biobank set up 40 years ago is still reaping scientific fruit today in unimagined ways, through international collaboration."
The research was supported by the Autism Research Trust, the Medical Research Council, and Wellcome.
Story Source:
Materials provided by University of Cambridge. 
Note: Content may be edited.

Comments

Popular posts from this blog

Size matters: New data reveals cell size sparks genome awakening in embryos

Transitions are a hallmark of life. When dormant plants flower in the spring or when a young adult strikes out on their own, there is a shift in control. Similarly, there is a transition during early development when an embryo undergoes biochemical changes, switching from being controlled by maternal molecules to being governed by its own genome. For the first time, a team from the Perelman School of Medicine at the University of Pennsylvania found in an embryo that activation of its genome does not happen all at once, instead it follows a specific pattern controlled primarily by the various sizes of its cells. The researchers published their results this week as the cover story in  Developmental Cell . In an early embryo undergoing cell division, maternally loaded RNA and proteins regulate the cell cycle. The genomes of the zygote -- a term for the fertilized egg -- are initially in sleep mode. However, at a point in the early life of the embryo, these zygotic nuclei "wake...

Home births as safe as hospital births: International study suggests

A large international study led by McMaster University shows that low risk pregnant women who intend to give birth at home have no increased chance of the baby's perinatal or neonatal death compared to other low risk women who intend to give birth in a hospital. The results have been published by  The Lancet 's  EClinicalMedicine  journal. "More women in well-resourced countries are choosing birth at home, but concerns have persisted about their safety," said Eileen Hutton, professor emeritus of obstetrics and gynecology at McMaster, founding director of the McMaster Midwifery Research Centre and first author of the paper. "This research clearly demonstrates the risk is no different when the birth is intended to be at home or in hospital." The study examined the safety of place of birth by reporting on the risk of death at the time of birth or within the first four weeks, and found no clinically important or statistically different risk between home...

Molecular adlayer produced by dissolving water-insoluble nanographene in water

Molecular adlayer produced by dissolving water-insoluble nanographene in water : "Nanographene incorporated micelle capsules" can be prepared by simply pulverizing and mixing nanographene with amphiphilic V-shaped anthracene molecules in water at room temperature. Even though nanographene is insoluble in water and organic solvents, Kumamoto University (KU) and Tokyo Institute of Technology (Tokyo Tech) researchers have found a way to dissolve it in water. Using "molecular containers" that encapsulate water-insoluble molecules, the researchers developed a formation procedure for a nanographene adlayer, a layer that chemically interacts with the underlying substance, by just mixing the molecular containers and nanographene together in water. The method is expected to be useful for the fabrication and analysis of next-generation functional nanomaterials. Graphene is a single layer of carbon atoms arranged in sheet form. It is lighter than metal wit...