A new study reports on the potential for a saliva screening test for autism spectrum disorder. The study describes significantly altered proteins in children with autism spectrum disorder, providing a basis for future research and development of a saliva screening test.
Although the causes and underlying mechanisms of autism spectrum disorder (ASD) are not well understood, it has been reported that up to 1 in 50 children in the US may have ASD, with many cases potentially left undiagnosed. Behavioural tests are currently used to diagnose ASD, and there are no available biological screening tests.
In an effort to search for new biomarkers for ASD, researchers from the State University of New York Neuropsychology Clinic collected saliva samples from male participants aged between 5 and 17 years. Saliva was used in the study, as it is a rich source of proteins, containing almost as many proteins as blood plasma (approximately 2,290 proteins, compared with blood plasma that contains approximately 2,698 proteins), however, can be obtained less invasively than a blood sample. The saliva was processed and analyzed using nano liquid chromatography–tandem mass spectrometry.
There were differences in several proteins found between the control group and the ASD group. The researchers noted that the proteins that tended to be elevated in the ASD group are some that are involved in both immunological responses and inflammation. These proteins included: lactoferrin, prolactin inducible protein, Ig gamma-1 chain C region and Ig kappa chain C region, neutrophil elastase, and polymeric immunoglobulin receptor.
The researchers suggest that this panel of proteins found to be increased in ASD patients could not only serve as potential biomarkers for detecting the disorder, but may provide further insight into the biological processes that may be involved. The researchers aim to continue their work, studying the protein array in a greater number ASD patients.
The Children’s Hospital Boston, in collaboration with the National Institute of Neurological Disorders and Stroke (NINDS), and Tuberous Sclerosis Alliance is currently recruiting participants for a study investigating early biomarkers for autism. Approximately 150 infants aged between 3 and 12 months who have been diagnosed with tuberous sclerosis complex (TSC) will be enrolled in the study. Infants with TSC are being enrolled since autism is common in this population. The researchers will assess the infants using behavioural tests, MRI, and EEG to identify developmental precursors to ASD. MRI biomarkers will be used to characterize brain tissue, including whit matter structure and connectivity, functional networks, and pathology. The study is anticipated to take approximately 5 years.
NgounouWetie, AG, Wormwood, KL, Russell, S, Ryan, JP, Darie, CC, Woods, AG. “A Pilot Proteomic Analysis of Salivary Biomarkers in Autism Spectrum Disorder” Autism Research Article first published online: 27 Jan 2015 DOI: 10.1002/aur.1450
Clinicaltrials.gov “Early biomarkers of Austism in Infants With Tuberous Sclerosis Complex” Available from: https://www.clinicaltrials.gov/ct2/show/NCT01780441term=autism+spectrum+disorder+AND+early+intervention&rank=15 Last Accessed: Feb 26, 2015.
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Written by Deborah Tallarigo, PhD