People with autism have been identified as having a different intestinal microbiome

A team of scientists confirmed that children with autism spectrum disorder (TEA) have a different intestinal microbiome than neurotypicals and discovered 31 biological markers that could help diagnose this disorder.

Furthermore, the researchers believe that in the future these findings could help to discover whether some of these components of the intestinal microbiome and their functions could contribute to causing autism.

The study, whose details were published yesterday in the journal “Nature Microbiology”was carried out by a team of Chinese scientists led by Siew Ng, of the Chinese University de Hong Kong (China).

The intestinal microbiome is the set of microorganisms that live in the human intestine (microbiota), with their genes and metabolites. It has long been known that there is a relationship between the gut microbiome and ASD However, until now, most studies have focused on intestinal bacteria and have not studied whether the archaea, fungi and viruses of the microbiome, their function or their genes are altered in ASD.

To find out, the researchers conducted the metagenomic sequencing of fecal samples from 1,627 children with or without ASD between one and 13 years of age from five cohorts in China.

The authors analyzed these samples along with data on additional factors such as diet, medication, and comorbidity and identified 14 archaea, 51 bacteria, 7 fungi, 18 viruses, 27 microbial genes, and 12 metabolic pathways altered in children with ASD.

Then, using machine learning, they created a model based on a panel of 31 microbes and functions, which had higher diagnostic accuracy in identifying people with ASD compared to gut microbiome marker panels based on a single kingdom (such as bacteria or archaea).

The authors suggest that these 31 markers could have clinical diagnostic potential given their reproducibility across multiple cohorts. These findings may also aid future work to study the relationship between gut microbiota and ASD diagnosis.

Repercussions of the study

To Bhismadev Chakrabarti, Research Director of the Autism Centre at the University of Reading (United Kingdom), the study is important because for the first time it analyzes the role of fungi, archaea and viruses in autism.

“Overall, the results are in line with those of previous studies, which show a lower microbial diversity in autistic people. Furthermore, it is based on one of the largest samples seen in a study of this type, which further reinforces the results,” he said in a statement to the SMC.

And while the study found no evidence that microbiota causes autism, it “opens up the possibility of investigating specific biochemical pathways and their impact on different autistic traits” in the future.

In addition, he stresses, “it could provide new ways to detect autism, if microbial markers strengthen the capacity of genetic and behavioral tests to detect autism.”

Along the same lines, Toni GabaldonICREA research professor and head of the Comparative Genomics group at the Institute for Research in Biomedicine (IRB Barcelona) and the Barcelona Supercomputing Centre (BSC-CNS), highlights that the study is based on a large number of samples and also takes into account other dietary and lifestyle factors that affect the intestinal microbiome.

It has been known for some time that children with autism spectrum disorder have a different intestinal microbiota, but most studies have been based on the study of bacteria. This study “provides a much more complete view of the metabolic changes associated with changes in microbiota,” the Spanish researcher highlights.

On the discovery of the 31 biomarkersGabaldón recalls that currently the diagnosis is based on behavioral patterns that appear over time, so “having early biomarkers that could help detect autism earlier could facilitate the initiation of earlier therapies.”

“If there are metabolic changes that influence the progression of symptoms and could be compensated by diet or the use of probiotics, modulating the microbiota would open the door to new treatments that improve some aspects,” highlights Gabaldón.