Gut microbiota may unlock new diagnostic and treatment strategies for autism

Gut microbiota biomarkers show >90 percent sensitivity and specificity in diagnosing autism spectrum disorder (ASD). Gut microbiome modulation with a novel synbiotic formula, SCM06, may alleviate anxiety symptoms in children with ASD, according to researchers from the Chinese University of Hong Kong (CUHK).

31-microbiome panel for ASD diagnosis

“Diagnosis of ASD is challenging and often delayed, especially in younger children with mild symptoms,” said Professor Siew Ng, Co-director of the Microbiota I-Center, CUHK.

Gut microbiome plays a central role in modulating the gut-brain axis and may contribute to the development of ASD. Therefore, the researchers investigated the difference in faecal biomarkers in 1,627 Chinese children with or without ASD (age, 1–12 years; female, 24.4 percent) in a cohort study. [Nat Microbiol 2024;doi:10.1038/s41564-024-01739-1]

Results showed delayed gut maturity in children with ASD, with differences in 51 bacteria, 27 microbial genes, 18 viruses, 14 archaea, 12 metabolic pathways, and seven fungi in children with vs without ASD. “Most prior studies focused on the bacterial component, our results confirmed the contribution of other microbiome components in ASD,” commented Dr Qi Su of the Department of Medicine and Therapeutics, CUHK.

Using a machine learning model, the researchers developed a noninvasive diagnostic tool comprising a panel of 31 multikingdom and functional gut microbiota biomarkers. “Our panel demonstrated high accuracy in diagnosing ASD, with a sensitivity of 94 percent and a specificity of 93 percent,” reported Su. “It was validated across two independent cohorts: hospital cohort [age, 4–11 years] and community cohort [age, 1–8 years], demonstrating a sensitivity of 91 percent in both cohorts,”

SCM06 for ASD treatment

Gamma-aminobutyric acid (GABA) is a major inhibitory neurotransmitter in the central nervous system associated with sensory hypersensitivity and anxiety. The researchers recently completed a pilot study investigating the use of a novel synbiotic formula, SCM06, to boost the abundance of GABA in 30 children with ASD (age, 4–11 years; male, 73 percent). [Neuropsychiatr Dis Treat 2015;11:165-175; Wong WH, 2024]

Preliminary findings indicated that children with ASD who received SCM06 for 12 weeks showed an overall 15–20 percent reduction in sensory and anxiety symptoms, with no adverse events observed.

“Given that there are limited ASD treatment options and potential side effects associated with some medications, our results are encouraging and suggest that modulation of the gut microbiome represents a new, safe treatment approach for ASD,” said Dr Oscar Wong of the Department of Psychiatry, CUHK.

On to the next phases

The CUHK researchers are working on large-scale clinical trials to provide further evidence on the clinical efficacy of SCM06 and the diagnostic potential of the 31-microbiome panel (The PROMISE study).

The PROMISE study aims to recruit 1,000 children aged ≤4 years with suspected/diagnosed ASD or other developmental problems whose parents are either Chinese or Asian. Those interested in the study may contact the research team by phone at 2607 6037 or via WhatsApp at 6099 3064.