Testosterone levels and autism:

Simon Baron-Cohen of Cambridge University argues that the level of testosterone to which a fetus is exposed in the womb is important. To test this theory, his team made use of Denmark’s unusual practice of storing amniotic fluid when a pregnant woman has undergone tests, linking this information with the country’s national register of people diagnosed with psychiatric symptoms. They found a correlation between autism and elevated levels of testosterone in the womb. “Nature was giving us a clue,” says Mr Baron-Cohen, pointing to the male bias in the incidence of autism.
- Youthful folly, Economist, July 9, 2015

Nobody is sure what causes autism. One theory points the finger at something called the “cellular danger response”. This involves compounds known as purines, which command cells to halt their usual activities and brace for an imminent viral attack. That response is normal and, provided it switches off when the danger has passed, beneficial. But some researchers believe that the mechanism can end up switched on permanently. This, they think, can encourage the development of autism. ...
Dr Naviaux’s past work with mice shows that when mothers are exposed to a virus-like stress while pregnant, the cellular danger responses of their pups can become permanently activated. And one side-effect of the response is to inhibit the growth of neural connections that is normal in young brains. The result is a set of behaviours—difficulty with social situations, and a strong preference for familiar things and for routine—that bear a strong resemblance to autism in humans.
- A drug used to treat sleeping sickness may also help with autism, Economist, June 3, 2017

Americans may have lost half their microbial diversity in recent decades. ...
Research also points to a strong link between this loss, especially in early life, and the epidemic-level increase of many terrible diseases and disorders. ... And evidence grows that diminished microbial diversity may trigger or worsen inflammatory bowel diseases, diabetes, food allergies and autism.
- Sarah Schenck, Save the Germs, NYT, Nov. 18, 2018

Show php error messages