A new study shows a link between a lack of beneficial bacteria in the gastrointestinal tract and autism in children.
“One of the reasons we started addressing this topic is the fact that autistic children have a lot of GI problems that can last into adulthood,” said Rosa Krajmalnik-Brown, Ph.D., who led the research team at Arizona State University’s Biodesign Institute.
“Studies have shown that when we manage these problems, their behavior improves dramatically.”
Following up on these hints, the research team hypothesized that the intestinal microflora found in autistic children would be different when compared to that of healthy children.
The new study confirmed these suspicions, finding that children with autism had significantly fewer types of gut bacteria. They also had significantly lower amounts of three critical bacteria: prevotella, coprococcus and veillonellaceae, according to the researchers.
For the study, the researchers analyzed the intestinal microflora in fecal samples from 20 healthy and 20 autistic children between the ages of 3 and 16. The samples were analyzed using a technique known as pyrosequencing, which allows many DNA samples to be combined, as well as many sequences from each sample to be analyzed.
The researchers found a correlation between a lower diversity of intestinal microbes and the presence of autistic symptoms.
According to the researchers, “bacterial richness and diversity are essential for maintaining a robust and adaptable bacterial community capable of fighting off environmental challenges.”
“We believe that a diverse gut is a healthy gut,” Krajmalnik-Brown said.
Prevotella was the most conspicuously reduced in autistic subjects, according to the analysis. It is believed to play a key role in the composition of the human gut microbiome.
For this reason, the researchers undertook a further investigation of the samples from the autistic children. They found that a bacteria known as prevotella copri occurred only in very low levels in the samples from the autistic children.
“We think of prevotella as a healthy, good thing to have,” Krajmalnik-Brown noted.
Jin Gyoon Park, lead author of the study with Dae-Wook Kang, noted he believe the microbiome can be mined in the future to find diagnostic biomarkers for autism and other diseases.
Next up for the researchers is a more detailed, gene-level analyses aimed at probing bacterial function.
The researchers added they also will use the results from the current study as a guide for new treatment studies for autism, aimed at modifying bacterial composition in the gut.
The study was published in the journal PLOS ONE.
Source: Arizona State University