Half of your genes come from your mother, and new research suggests you may also get your gut bacteria from her too. Scientists studied wild primates, called geladas, to find the first evidence of a maternal influence on the gut development of offspring, even after weaning.
The research team from Arizona State University used DNA sequencing to identify 3,784 genetic strains of bacteria inside the young geladas. The bacterial strains belonged to 19 phyla and 76 different families. Despite the variety of bacteria, the researchers observed that they did not have this diversity from the very start.
Like human infants, the geladas show the least amount of microbial diversity when they are born and gradually build up a more diverse portfolio as they get older. The different bacterial strains reflected what the infant ate, specifically their diet of solid food after relying on breast milk during infancy.
However, the most revolutionary finding came from when biologists inspected the infant gut microbiome after weaning. Infants from first-time mothers took a slower time diversifying their microbiomes as their guts were more equipped to digest milk than kids with other mothers. After weaning, the infants’ microbiome was similar to their mother’s compared to other adult females in their communities.
The findings suggest the maternal geladas share their gut bacteria with their offspring.
“Early life gut microbial development is known to have a large impact on later life health in humans and other model organisms,” notes Amy Lu, an associate professor of anthropology at Stony Brook University and study coauthor, in a media release. “Now we have solid evidence that mothers can influence this process, both before and weaning.”
Researchers did not uncover why this happens, but Dr. Lu hypothesizes that the mother transfers specific bacteria, possibly through breast milk, to their offspring.
“These early life changes might have far-reaching consequences–impacting the health and survival of these offspring once they become adults,” adds Noah Snyder-Mackler, an anthropologist at Arizona State University and study co-author.
The team is looking to expand on their findings with future projects focusing on how differences in the microbiome during infancy influence later growth, such as the maturation of the immune system or reproductive behavior. Since the researchers are monitoring the infant primates as they grow up, they’ll eventually be able to study the maternal effects of the infant gut microbiome on their overall health and survival in adulthood.
The study is published in Current Biology.