Saliva Test Shows Promise For Diagnosing Autism
With the publication of a new study, a saliva test one day may provide a way to diagnose autism early in children.
The study, published in the journal Autism Research, is the first showing that protein levels in the saliva of children with autism spectrum disorder differ from those without it, according to researchers at Clarkson University.
“We are the first in the world who proposed a protein complex as a potential biomarker signature, which gives us information not only about the proteins, their relative quantities and their modifications, but also about their interactions with other proteins,” said Costel C. Darie, a lead author of the study and a Clarkson assistant professor of chemistry and biomolecular science.
Using a technique known as mass spectrometry to measure protein differences, researchers from Clarkson University and the State University of New York at Plattsburgh studied saliva from six children ages 6 to 16 diagnosed with autism, comparing the results with a control group of six typically-developing children of similar ages.
“We found nine proteins that were significantly elevated in the saliva of the people with autism and three that were lower or even absent,” said Alisa G. Woods, one of the leaders of the study and a researcher at both universities.
She said when proteins bind together in a system, suggesting they have a function, they may affect autism symptoms, such as repetitive behavior. She also said the combination of protein levels could be seen as a signature that points to symptoms of autism disorders.
“You could say it’s a signature of proteins. We look for protein X to go down along with protein Y and protein Z, but protein A and B will go up, and that whole signature of changes will help you make that diagnosis,” she said. “We think that’s probably going to be more realistic in terms of a test versus saying it’s just one thing.”
Woods said saliva was selected for testing because it is easy to obtain, and doesn’t inspire fear.
“If you took blood, that troubles children, so this is kind of a noninvasive, non-disturbing technique,” she said. “The kids really don’t ever mind this.”
Though more subjects need to be studied, if proven effective, the saliva test could be performed on infants, according to Woods.
She said the researchers are continuing to study saliva protein differences, having expanded to analyzing 32 children split into two groups — 16 with autism and 16 who are developing normally.
Subjects in that study also are undergoing a behavioral test at SUNY Plattsburgh, performed by Jeanne P. Ryan, clinical director and neuropsychologist. The results of that test will be compared to the saliva test.
With additional grant funding, Woods said, the researchers plan to conduct an even larger study with two groups of 40 people, which would involve collaborating with staff at the University of California, Davis MIND Institute, Vanderbilt University and SUNY Buffalo.