A new study published in *The Journal of Immunology* suggests a strong link between gut microbiota and autism development—particularly the mother’s microbiome. “The microbiome can shape the developing brain in multiple ways,” said lead researcher John Lukens from the University of Virginia. He added, “It’s important for how the offspring’s immune system responds to infection or stress.”

The study focused on a molecule called interleukin-17a (IL-17a), which is produced by the immune system and affects brain development in the womb. IL-17a has also been linked to diseases like psoriasis and multiple sclerosis.

Researchers tested mice from two labs: one group had gut bacteria that triggered inflammation via IL-17a; the other did not. When IL-17a was suppressed, all pups showed typical behavior. But when IL-17a was active, pups from the first group developed autism-like symptoms.

To confirm the role of microbiota, researchers transplanted feces from the first group into the second group. The second group’s pups then developed similar neurological issues, pointing to the mother’s gut bacteria as a key factor.

Though early and animal-based, the findings highlight the potential importance of maternal gut health in autism. Lukens said the next step is to study human microbiomes for similar patterns.