Recent research highlights a strong connection between gut microbiota and overall health—including its potential role in autism development.

A study in *The Journal of Immunology* suggests that the mother’s gut bacteria may influence autism risk more than the child’s own. “The microbiome can shape the developing brain in multiple ways,” said John Lukens, lead researcher from the University of Virginia.

The key may lie in a molecule called interleukin-17a (IL-17a), produced by the immune system. It plays a known role in diseases like psoriasis and rheumatoid arthritis, and may also affect brain development in the womb.

Using mice, scientists found that those exposed to gut bacteria triggering strong IL-17a responses developed autism-like behaviors, such as repetitive actions. When IL-17a was suppressed early on, the behavior did not appear—until the treatment stopped. Later, even mice without the condition began showing symptoms after receiving fecal transplants from affected mice.

Though still early-stage, the findings raise hope for future research. “The next big step would be to identify features of the microbiome in pregnant mothers that correlate with autism risk,” said Lukens. However, he warns against altering immune responses during pregnancy, calling it “a complex balance of immune regulation.”