A spit test one day might be able to diagnose autism, according to a pilot study that showed children with autism spectrum disorder have differences in saliva protein levels when compared with typically developing children.
Scientists at Clarkson University in Potsdam, N.Y., and the State University of New York at Plattsburgh published results from a small study in the Jan. 27 issue of the journal Autism Research.
ASD affects one in 68 children in the U.S., according to CDC estimates, and the number of people diagnosed with autism continues to rise. Diagnosis is made based on behavioral observations, and no biological test for ASD exists. A biological test could aid in earlier diagnosis, helping to direct people with autism to interventions.
The researchers, led by Clarkson doctoral candidate Armand Gatien Ngounou Wetie, studied saliva from six children diagnosed with autism ages 6-16, compared with six typically developing children in the same age range. They used mass spectrometry to measure protein differences in saliva taken from the two groups, according to a news release.
“We found nine proteins that were significantly elevated in the saliva of the people with autism and three that were lower or even absent,” co-investigator Alisa G. Woods, PhD, a researcher at Clarkson and the SUNY Plattsburgh Center for Neurobehavioral Health, said in the release. “This is the first study to identify these changes in saliva, which is a relatively easy biofluid to obtain for clinical use or research.”
The proteins identified primarily have functions in immune system responses or are elevated in people with gastrointestinal problems, according to the release. The scientists also reported several of the identified proteins interact with one another.
“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,” co-lead author Costel C. Darie, PhD, an assistant professor of chemistry and bimolecular science at Clarkson and proteomics expert, said in the release.
The work is promising for the eventual development of a diagnostic test, but more subjects need to be studied to confirm the markers are consistently different in people with autism, the researchers said.
“We have found some interesting proteins that are different from children with autism compared with controls, and I think the next stage would be to increase the pool of samples to confirm those findings,” Ngounou said in the release.
The group plans to further study these protein differences in larger groups of children with ASD and also in specific subtypes of ASD.