Child's Risk of Autism Can Change Based on Health of Mother's Gut

The microbiome can be changed by a mother by adjusting what she eats, such as by increasing consumption of good bacteria, or probiotics, like those found in yogurt, to make it healthier. PIERRE ALBOUY/REUTERS

New research suggests that the risk of developing autism is determined by the mother's gut during pregnancy.

Scientists at the University of Virginia School of Medicine were able to analyze pregnant women's microbiomes to determine the child's risk of developing autism. The study, published July 2 in The Journal of Immunology, also researched how to use this finding to halt the development of autism-like neurodevelopmental disorders in mice.

"Our study was interested in understanding how the microbiome, which is the community of microbes that live within our gut, can shift susceptibility to autism-spectrum disorder," John Lukens, assistant professor at the University of Virginia and lead author on the study, told Newsweek. To do this, the team studied, in part, interleukin-17a.

"It's kind of the middleman between the gut and the brain," Lukens says. Scientists at the Massachusetts Institute of Technology found that the inflammatory molecule interleukin-17a, or IL-17a, can influence the development of autism-like disorders in the brain. IL-17a has also been found to influence the development of multiple sclerosis and rheumatoid arthritis.

"What it can do during pregnancy is alter how the brain is developed and wired," Lukens explains. This is what causes it to increase the chances of a child having an autism-spectrum disorder. The UVA team found that by blocking IL-17a in mice, which is produced by the immune system, chances of developing autism-spectrum disorders also decreased. The good news is the team also found that a healthy microbiome can block IL-17a.

The microbiome can be changed by a mother by adjusting what she eats, such as by increasing consumption of good bacteria, or probiotics, to make it healthier. Most immune cells, like IL-17a, actually develop around the gut. This research means that a mother may be able to prevent certain disorders on the autism spectrum just by eating differently. However, the scientists warn that blocking IL-17a might end up being risky.

"Although we know IL-17a can shape brain development, it's also very important in terms of fighting infection," Lukens explains. Since IL-17a comes from the immune system, trying to change the immune system during pregnancy may put the mother and fetus at risk for those infections. This means that people shouldn't start to specifically try to block IL-17a just yet, such as through targeted treatments. However, "the probiotics diet could go forward pretty quickly, like through having a balanced diet and taking Vitamin D," Lukens says.

There is still a lot to find out when it comes to the development of autism-spectrum disorders, but Lukens points out, "What our data really indicates is that gestational health is very important to all forms of development, especially the brain."