I know they are finding imbalances in the gut mircrobiome are associated with a variety of condition. I thought the study design was a bit curious though.

"In this study, fecal microbiota transplant (FMT) via gavage from autistic children donors to mice, led to the colonization of ASD-like microbiota and autistic behaviors compared to the offspring of pregnant females exposed to valproic acid (VPA)."

I don't doubt that they were able to get mice to exhibit autism by altering the microbiome, I've seen them do similar things with other conditions, but one would think the controls would just be healthy mice that simply hadn't been given FMT, yet for some reason they were exposed to valproic acid, brand name Depakote, which is used as a mood stabilizer and anti-seizure medication. This seems like a very strange control group to me, although there may be a good reason for this. I tried checking Sci-Hub for this one to see behind the paywall, but they don't seem to have it.