The bacteria lurking in childrens’ guts could trigger autism, research suggests.
A study found youngsters with autism spectrum disorder (ASD) have a unique make-up of bugs in their stools.
These abnormalities may come from the youngsters’ mothers, who were also found to carry higher levels of certain bacterial strains.
Researchers believe these bacteria may produce substances that block the delivery of chemical messages, which could trigger ASD’s onset.
The bugs may also induce inflammation that may lead to the disorder, the scientists have speculated.
The bacteria lurking in our guts could trigger autism, research suggests (stock)
On the back of their study, they hope manipulating a patient’s gut bacteria could one day treat, or even prevent, autism.
The study was carried out by the Qilu Children’s Hospital of Shandong University in Jinan, China, and led by Ning Li, a researcher in the microbiome centre.
Around one in 59 children in the US has ASD, with boys being four times more at risk, according to the Center for Disease Control and Prevention.
And in the UK, more than one in 100 people have the condition, National Autistic Society statistics show.
The condition is notoriously difficult to diagnose and treat because the cause is currently unclear. Its prevalence is on the rise worldwide.
Emerging research links ASD to genetics, however, DNA alone is not thought to be the ‘underlying cause’ in most cases.
Obesity, stress and infections during pregnancy have been linked to ASD’s onset. However, none have been proven.
A mother’s bacterial gut make-up may also influence her child’s risk of the disorder, studies are also beginning to suggest.
THE SIGNS AND SYMPTOMS OF AUTISM
According to the Centers for Disease Control and Prevention, people with autism have trouble with social, emotional and communication skills that usually develop before the age of three and last throughout a person’s life.
Specific signs of autism include:
- Reactions to smell, taste, look, feel or sound are unusual
- Difficulty adapting to changes in routine
- Unable to repeat or echo what is said to them
- Difficulty expressing desires using words or motions
- Unable to discuss their own feelings or other people’s
- Difficulty with acts of affection like hugging
- Prefer to be alone and avoid eye contact
- Difficulty relating to other people
- Unable to point at objects or look at objects when others point to them
This is thought to occur via the ‘gut-brain axis’, which communicates through our nervous, hormonal and immune systems.
It has been suggested an imbalance to an expectant mother’s microbiome may affect her child’s central nervous system, which could lead to ASD.
Human and rat studies have also shown altering the microbiome by introducing ‘good bacteria’ can reduce ASD symptoms.
To uncover whether a mother’s gut bacteria influences her child’s ASD risk, the researchers analysed the stools of 59 youngsters with the disorder, as well as their mothers’ faeces.
These were compared against faeces samples provided by 30 mother-child pairs where the youngsters did not have ASD.
Results revealed both the children with ASD and their mothers had a significant ‘increase in bacterial richness’.
The youngsters with the disorder had higher levels of the bacteria Alcaligenaceae, Enterobacteriaceae, and Clostridium.
And their mothers had greater concentrations of Proteobacteria, Moraxellaceae, Alphaproteobacteria and Acinetobacter.
Identifying these bacteria could help doctors diagnose children who are thought to have ASD, the researchers claim.
They stress, however, larger studies should look at how the order of change to a pregnant woman’s gut bacteria may influence her child’s autism risk.
The study also did not assess the women’s fibre intake, living conditions or history of gut problems, which may influence their microbiome.
The findings were published in the journal Genomics, Proteomics & Bioinformatics.