Analysis of gut microbiota profiles and microbe-disease associations in children with autism spectrum disorders in China Original paper

What was studied?

This original research article examined gut microbiota in children with ASD using 16S rRNA sequencing to characterize fecal microbial composition and explore potential microbial signatures linked to autism spectrum disorder in a Chinese pediatric cohort. The investigators aimed to clarify how specific bacterial taxa, functional metabolic pathways, and microbe-disease similarity patterns differ between ASD and typically developing children. They also integrated microbiome findings with a human microbe–disease association database to assess how ASD-related microbial shifts align with patterns seen in other diseases, producing a microbe-based disease network that highlights potential mechanistic overlaps.

Who was studied?

The study included 35 children with ASD and 6 typically developing controls, all aged 3–8 years, after quality filtering of stool samples. Participants were recruited from Beijing and diagnosed according to DSM-5 criteria. Exclusion criteria included genetic syndromes, inflammatory conditions, special diets, antibiotic or probiotic use, and psychiatric comorbidities in the control group. Stool samples were parent-collected, deep frozen, and processed for sequencing using Illumina HiSeq paired-end reads.

Most important findings

Microbiota structure differed clearly between groups, with ASD samples clustering apart from controls in beta-diversity analyses. The ASD group showed a significantly elevated Bacteroidetes/Firmicutes ratio, driven by increased Bacteroidetes abundance. Several genera showed marked reductions in ASD, including Streptococcus, Veillonella, and Escherichia. These taxa are important for lactate metabolism, and their loss suggests impaired microbial fermentation. The study also identified decreased abundance—though not statistically significant—of butyrate-producing genera such as Faecalibacterium and Roseburia, which play a key role in maintaining epithelial integrity and anti-inflammatory signaling. Functional prediction using KEGG pathways revealed enrichment of bacterial chemotaxis, phosphotransferase systems, and prion-disease–related pathways in ASD, whereas steroid hormone biosynthesis and lipoic acid metabolism were enriched in controls.

A notable systems-level finding was the microbe-based disease network. ASD exhibited a positive microbial similarity with periodontitis, supported by shared reductions in oral-associated taxa. Conversely, ASD showed negative similarity with type 1 diabetes, aligning with opposite patterns in genera such as Veillonella.

Key implications

The study underscores that gut microbiota disruptions in ASD extend beyond simple taxonomic shifts, involving functional metabolic alterations and disease-relevant microbial signatures. Reduced lactate and butyrate producers imply weakened mucosal barrier support and altered gut–brain axis signaling, potentially contributing to gastrointestinal and neurobehavioral symptoms. The disease similarity network further suggests that microbiome-based phenotyping may help identify ASD subtypes and reveal mechanistic links between ASD and comorbid or oppositely associated diseases. This work highlights the clinical relevance of microbiome-informed approaches in ASD and encourages exploration of microbiota-targeted interventions.

Citation

Zhang M, Ma W, Zhang J, He Y, Wang J. Analysis of gut microbiota profiles and microbe-disease associations in children with autism spectrum disorders in China.Scientific Reports. 2018;8:13981. doi:10.1038/s41598-018-32219-2