Study Highlights Neurotransmitter Pathway Variations and Potential Role of Oral Microbiome in Autism Understanding
A study analyzing 7,812 oral microbiomes from 2,025 U.S. families in the SPARK-WGS cohort identified significant differences in salivary microbiomes between children with autism spectrum disorder (ASD) and neurotypical (NT) individuals, with cognitive impairment emerging as a key driver of these differences. The study found ASD children exhibited lower microbial strain sharing with parents, especially in those with severe to moderate cognitive impairment (IQ ≤ 70). Key differences included altered metabolic pathways related to neurotransmitter degradation, with ASD samples showing enrichment in GABA degradation to butyrate and serotonin metabolism, while NT samples showed increased glutamate degradation and direct butyrate synthesis. Lifestyle factors like diet and oral hygiene were less influential than cognitive function, suggesting that cognitive impairments mediate the observed microbiome differences. The findings underscore the potential of the oral microbiome as a biomarker for ASD-related cognitive deficits and highlight the need for further studies to explore its systemic effects and connections to the gut-brain-microbiome axis.