The finding, that the microbiome (the collection of microorganisms in and on the human body) may play a role with some types of autism is based on studies using mice.
Autism is classed as disorder of neural development. There is not one type of ‘autism’, rather a spectrum of different behaviors. The condition is characterized by inhibited verbal and non-verbal communication, and by problems with social interaction, such as restricted, or repetitive behaviors.
The new research follows on from earlier work that draws a link between maternal obesity and an increased risk for autism in children. Here gastrointestinal problems are common among those with autism and the gut is known to communicate extensively with the brain.
On this basis Professor Shelly Buffington, from Baylor College of Medicine, has undertaken research to see if gut microbiota play a role in the behavioral characteristics of autism.
Speaking with Bioscience Techniques, Professor Buffington said: “we wanted to see whether there was a difference in the microbiome between the offspring of mouse mothers fed a normal diet versus those of mothers fed a high-fat diet.”
To test for this, studies were performed using mice. Populations of female mice were fed either a high fat diet or a regular diet and then paired with males to produce pups. The pups were fed a standard diet. The pups from obese mothers showed the characteristics akin to forms of autism.
When the fecal matter from the mice was examined, using molecular sequencing methods, the microbial populations were different. The mice displaying autism like behaviors, together with the female mice fed the high fat diet, had a lower diversity of microorganisms.
The organism found in lower numbers was Lactobacillus reuteri. The next wave of research will examine the effect this organism plays on human development in greater detail.
The research has been published in the journal Cell. The research paper is titled “Microbial Reconstitution Reverses Maternal Diet-Induced Social and Synaptic Deficits in Offspring.”
The new research extends further the importance of the microbiome to human health and development. The bacteria in the human gut and the way that the types and numbers change have been linked to a range of conditions, Pharmaceutical Microbiology reports. These range from digestion, body weight, regulating immune response, and producing neurotransmitters that affect brain and behavior.
It should be noted that the findings are preliminary and what happens with mice does not necessarily translate to people, especially in the context of the complexity of autism.