Researchers at the UC Davis MIND Institute and NeuroPointDX have found a group of blood metabolites that could lead to a reliable biomarker test for detecting autism spectrum disorder (ASD) in children.
Currently, no such biomarker test exists for the developmental disorder and behavioral patterns for diagnosis does not become evident until 2-4 years of age. As a result, researchers have turned to metabolomics in hopes of establishing the first test to accelerate diagnosis.
“By the time you’re getting to metabolomics, you’re looking at how the body is working, not just the genes it has,” said David G. Amaral, the director of research at the MIND Institute.
As part of the Children’s Autism Metabolome Project (CAMP), the largest metabolomic study for identifying diagnostic signatures, 1,100 children – 516 with ASD – aged 18 to 48 months, were recruited from various centers across the U.S.
Participants underwent physical, neurological and behavioral examinations. Blood samples and medical histories were also collected. Blood metabolites, particularly amino acids (AA), were compared in the CAMP sample of 516 children with ASD and 164 demonstrating typical development.
“Dysregulation of AA metabolism was identified by comparing plasma metabolites from 516 children with ASD with those from 164 age-matched typically-developing (TYP) children recruited into CAMP. ASD subjects were stratified into subpopulations based on shared metabolic phenotypes associated with branch chain amino acids (BCAA) dysregulation,” the study reads.
According to the findings, 17 percent of the children with ASD showed concentrations of specific amino acids in their blood samples. “We identified groups of AAs with positive correlations that were, as a group, negatively correlated with BCAA levels in ASD. Imbalances between these two groups of AAs identified three ASD associated Amino Acid Dysregulation Metabotypes (AADM).”
“The combination of glutamine, glycine, and ornithine AADMs identified a dysregulation in AA/BCAA metabolism that is present in 16.7% of the CAMP ASD subjects and is detectable with a specificity of 96.3% and a PPV of 93.5%.”
The detection and utilization of metabotypes of ASD may result in metabolic tests for early diagnosis and subsequent targeted therapeutic interventions, researchers say.
“The long-term vision is, once we’ve been able to analyze all the data from CAMP, we would have a series of panels,” Amaral proclaimed. “Each of these would be able to detect a subset of kids with autism. Ultimately, metabolomics may be able to identify most children with autism.”
The study was published in the journal Biological Psychiatry.